diff --git a/NAMESPACE b/NAMESPACE
index ff480db..a9c20b0 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -93,6 +93,7 @@ importFrom(clipr,read_clip)
 importFrom(curl,curl_unescape)
 importFrom(formatR,tidy_source)
 importFrom(jsonlite,fromJSON)
+importFrom(jsonlite,unbox)
 importFrom(lubridate,ymd_hms)
 importFrom(openssl,base64_decode)
 importFrom(scales,comma)
diff --git a/R/render-har.r b/R/render-har.r
index 7f76e5a..586e07c 100644
--- a/R/render-har.r
+++ b/R/render-har.r
@@ -14,24 +14,24 @@ render_har <- function(splash_obj = splash_local, url, base_url, response_body=F
                        forbidden_content_types, viewport="1024x768", images, headers, body,
                        http_method, save_args, load_args) {
 
-  params <- list(url=url, timeout=timeout, wait=wait, viewport=viewport,
+  params <- list(url=url, timeout=timeout, wait=wait, viewport=jsonlite::unbox(viewport),
                  response_body=as.numeric(response_body))
 
-  if (!missing(base_url)) params$base_url <- base_url
+  if (!missing(base_url)) params$base_url <- jsonlite::unbox(base_url)
   if (!missing(resource_timeout)) params$resource_timeout <- resource_timeout
-  if (!missing(proxy)) proxy$base_url <- proxy
-  if (!missing(js)) params$js <- js
-  if (!missing(js_src)) params$js_src <- js_src
-  if (!missing(filters)) params$filters <- filters
-  if (!missing(allowed_domains)) params$allowed_domains <- allowed_domains
-  if (!missing(allowed_content_types)) params$allowed_content_types <- allowed_content_types
-  if (!missing(forbidden_content_types)) params$forbidden_content_types <- forbidden_content_types
-  if (!missing(images)) params$images <- images
+  if (!missing(proxy)) params$proxy <- jsonlite::unbox(proxy)
+  if (!missing(js)) params$js <- jsonlite::unbox(js)
+  if (!missing(js_src)) params$js_src <- jsonlite::unbox(js_src)
+  if (!missing(filters)) params$filters <- jsonlite::unbox(filters)
+  if (!missing(allowed_domains)) params$allowed_domains <- jsonlite::unbox(allowed_domains)
+  if (!missing(allowed_content_types)) params$allowed_content_types <- jsonlite::unbox(allowed_content_types)
+  if (!missing(forbidden_content_types)) params$forbidden_content_types <- jsonlite::unbox(forbidden_content_types)
+  if (!missing(images)) params$images <- as.numeric(images)
   if (!missing(headers)) params$headers <- headers
-  if (!missing(body)) params$body <- body
-  if (!missing(http_method)) params$http_method <- http_method
-  if (!missing(save_args)) params$save_args <- save_args
-  if (!missing(load_args)) params$load_args <- load_args
+  if (!missing(body)) params$body <- jsonlite::unbox(body)
+  if (!missing(http_method)) params$http_method <- jsonlite::unbox(http_method)
+  if (!missing(save_args)) params$save_args <- jsonlite::unbox(save_args)
+  if (!missing(load_args)) params$load_args <- jsonlite::unbox(load_args)
 
   res <- httr::GET(splash_url(splash_obj), path="render.har", encode="json", query=params)
 
diff --git a/R/render-html.r b/R/render-html.r
index fcdc4bb..66d3d27 100644
--- a/R/render-html.r
+++ b/R/render-html.r
@@ -16,7 +16,7 @@
 #' @param allowed_domains Comma-separated list of allowed domain names. If present, Splash won’t load anything neither from domains not in this list nor from subdomains of domains not in this list.
 #' @param allowed_content_types Comma-separated list of allowed content types. If present, Splash will abort any request if the response’s content type doesn’t match any of the content types in this list. Wildcards are supported.
 #' @param forbidden_content_types Comma-separated list of forbidden content types. If present, Splash will abort any request if the response’s content type matches any of the content types in this list. Wildcards are supported.
-#' @param viewport View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is 1024x768.
+#' @param viewport View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is "full".
 #' @param images Whether to download images.
 #' @param headers HTTP headers to set for the first outgoing request.
 #' @param body Body of HTTP POST request to be sent if method is POST.
@@ -35,23 +35,23 @@ render_html <- function(splash_obj = splash_local, url, base_url, timeout=30, re
                         forbidden_content_types, viewport="1024x768", images, headers, body,
                         http_method, save_args, load_args, raw_html=FALSE) {
 
-  params <- list(url=url, timeout=timeout, wait=wait, viewport=viewport)
+  params <- list(url=url, timeout=timeout, wait=wait, viewport=jsonlite::unbox(viewport))
 
-  if (!missing(base_url)) params$base_url <- base_url
+  if (!missing(base_url)) params$base_url <- jsonlite::unbox(base_url)
   if (!missing(resource_timeout)) params$resource_timeout <- resource_timeout
-  if (!missing(proxy)) proxy$base_url <- proxy
-  if (!missing(js)) params$js <- js
-  if (!missing(js_src)) params$js_src <- js_src
-  if (!missing(filters)) params$filters <- filters
-  if (!missing(allowed_domains)) params$allowed_domains <- allowed_domains
-  if (!missing(allowed_content_types)) params$allowed_content_types <- allowed_content_types
-  if (!missing(forbidden_content_types)) params$forbidden_content_types <- forbidden_content_types
-  if (!missing(images)) params$images <- images
+  if (!missing(proxy)) params$proxy <- jsonlite::unbox(proxy)
+  if (!missing(js)) params$js <- jsonlite::unbox(js)
+  if (!missing(js_src)) params$js_src <- jsonlite::unbox(js_src)
+  if (!missing(filters)) params$filters <- jsonlite::unbox(filters)
+  if (!missing(allowed_domains)) params$allowed_domains <- jsonlite::unbox(allowed_domains)
+  if (!missing(allowed_content_types)) params$allowed_content_types <- jsonlite::unbox(allowed_content_types)
+  if (!missing(forbidden_content_types)) params$forbidden_content_types <- jsonlite::unbox(forbidden_content_types)
+  if (!missing(images)) params$images <- as.numeric(images)
   if (!missing(headers)) params$headers <- headers
-  if (!missing(body)) params$body <- body
-  if (!missing(http_method)) params$http_method <- http_method
-  if (!missing(save_args)) params$save_args <- save_args
-  if (!missing(load_args)) params$load_args <- load_args
+  if (!missing(body)) params$body <- jsonlite::unbox(body)
+  if (!missing(http_method)) params$http_method <- jsonlite::unbox(http_method)
+  if (!missing(save_args)) params$save_args <- jsonlite::unbox(save_args)
+  if (!missing(load_args)) params$load_args <- jsonlite::unbox(load_args)
 
   res <- httr::GET(splash_url(splash_obj), path="render.html", encode="json", query=params)
 
diff --git a/R/render-jpg.r b/R/render-jpg.r
index 3ac2c4f..6b8b2a6 100644
--- a/R/render-jpg.r
+++ b/R/render-jpg.r
@@ -8,32 +8,36 @@
 #' @references [Splash docs](http://splash.readthedocs.io/en/stable/index.html)
 #' @export
 render_jpeg <- render_jpg <- function(
-  splash_obj = splash_local, url, base_url=NULL, quality=75, width=1024, height=768,
-  timeout=30, resource_timeout, wait=0, render_all=FALSE,
+  splash_obj = splash_local, url, base_url=NULL, quality=75, width, height,
+  timeout=30, resource_timeout, wait=0, render_all=TRUE,
   proxy, js, js_src, filters, allowed_domains, allowed_content_types,
-  forbidden_content_types, viewport="1024x768", images, headers, body,
+  forbidden_content_types, viewport="full", images, headers, body,
   http_method, save_args, load_args) {
 
   params <- list(url=url, timeout=timeout,
                  wait=if (render_all & wait == 0) 0.5 else wait,
                  viewport=viewport,
-                 quality=quality, width=width, height=height, render_all=as.numeric(render_all))
+                 quality=quality,
+                 render_all=as.numeric(render_all))
 
-  if (!missing(base_url)) params$base_url <- base_url
+  if (!missing(width)) params$width <- width
+  if (!missing(height)) params$height <- height
+
+  if (!missing(base_url)) params$base_url <- jsonlite::unbox(base_url)
   if (!missing(resource_timeout)) params$resource_timeout <- resource_timeout
-  if (!missing(proxy)) proxy$base_url <- proxy
-  if (!missing(js)) params$js <- js
-  if (!missing(js_src)) params$js_src <- js_src
-  if (!missing(filters)) params$filters <- filters
-  if (!missing(allowed_domains)) params$allowed_domains <- allowed_domains
-  if (!missing(allowed_content_types)) params$allowed_content_types <- allowed_content_types
-  if (!missing(forbidden_content_types)) params$forbidden_content_types <- forbidden_content_types
-  if (!missing(images)) params$images <- images
+  if (!missing(proxy)) params$proxy <- jsonlite::unbox(proxy)
+  if (!missing(js)) params$js <- jsonlite::unbox(js)
+  if (!missing(js_src)) params$js_src <- jsonlite::unbox(js_src)
+  if (!missing(filters)) params$filters <- jsonlite::unbox(filters)
+  if (!missing(allowed_domains)) params$allowed_domains <- jsonlite::unbox(allowed_domains)
+  if (!missing(allowed_content_types)) params$allowed_content_types <- jsonlite::unbox(allowed_content_types)
+  if (!missing(forbidden_content_types)) params$forbidden_content_types <- jsonlite::unbox(forbidden_content_types)
+  if (!missing(images)) params$images <- as.numeric(images)
   if (!missing(headers)) params$headers <- headers
-  if (!missing(body)) params$body <- body
-  if (!missing(http_method)) params$http_method <- http_method
-  if (!missing(save_args)) params$save_args <- save_args
-  if (!missing(load_args)) params$load_args <- load_args
+  if (!missing(body)) params$body <- jsonlite::unbox(body)
+  if (!missing(http_method)) params$http_method <- jsonlite::unbox(http_method)
+  if (!missing(save_args)) params$save_args <- jsonlite::unbox(save_args)
+  if (!missing(load_args)) params$load_args <- jsonlite::unbox(load_args)
 
   res <- httr::GET(splash_url(splash_obj), path="render.jpeg", encode="json", query=params)
 
diff --git a/R/render-json.r b/R/render-json.r
index b796123..027684c 100644
--- a/R/render-json.r
+++ b/R/render-json.r
@@ -27,7 +27,7 @@
 #'       overwhelmed with data. Use [str()] to inspect various portions of the result.
 #' @references [Splash docs](http://splash.readthedocs.io/en/stable/index.html)
 #' @export
-render_json <- function(splash_obj = splash_local, url, base_url=NULL, quality=75, width=1024, height=768,
+render_json <- function(splash_obj = splash_local, url, base_url=NULL, quality=75, width, height,
                         timeout=30, resource_timeout, wait=0, render_all=FALSE,
                         proxy, js, js_src, filters, allowed_domains, allowed_content_types,
                         forbidden_content_types, viewport="1024x768", images, headers, body,
@@ -35,28 +35,31 @@ render_json <- function(splash_obj = splash_local, url, base_url=NULL, quality=7
                         iframes=TRUE, script=TRUE, console=TRUE, history=TRUE, har=TRUE,
                         response_body=FALSE) {
 
-  params <- list(url=url, timeout=timeout, wait=wait, viewport=viewport,
-                 quality=quality, width=width, height=height, render_all=as.numeric(render_all),
+  params <- list(url=url, timeout=timeout, wait=wait, viewport=jsonlite::unbox(viewport),
+                 quality=quality, render_all=as.numeric(render_all),
                  html=as.numeric(html), png=as.numeric(png), jpeg=as.numeric(jpeg),
                  iframes=as.numeric(iframes), script=as.numeric(script),
                  console=as.numeric(console), history=as.numeric(history), har=as.numeric(har),
                  response_body=as.numeric(response_body))
 
-  if (!missing(base_url)) params$base_url <- base_url
+  if (!missing(width)) params$width <- width
+  if (!missing(height)) params$height <- height
+
+  if (!missing(base_url)) params$base_url <- jsonlite::unbox(base_url)
   if (!missing(resource_timeout)) params$resource_timeout <- resource_timeout
-  if (!missing(proxy)) proxy$base_url <- proxy
-  if (!missing(js)) params$js <- js
-  if (!missing(js_src)) params$js_src <- js_src
-  if (!missing(filters)) params$filters <- filters
-  if (!missing(allowed_domains)) params$allowed_domains <- allowed_domains
-  if (!missing(allowed_content_types)) params$allowed_content_types <- allowed_content_types
-  if (!missing(forbidden_content_types)) params$forbidden_content_types <- forbidden_content_types
-  if (!missing(images)) params$images <- images
+  if (!missing(proxy)) params$proxy <- jsonlite::unbox(proxy)
+  if (!missing(js)) params$js <- jsonlite::unbox(js)
+  if (!missing(js_src)) params$js_src <- jsonlite::unbox(js_src)
+  if (!missing(filters)) params$filters <- jsonlite::unbox(filters)
+  if (!missing(allowed_domains)) params$allowed_domains <- jsonlite::unbox(allowed_domains)
+  if (!missing(allowed_content_types)) params$allowed_content_types <- jsonlite::unbox(allowed_content_types)
+  if (!missing(forbidden_content_types)) params$forbidden_content_types <- jsonlite::unbox(forbidden_content_types)
+  if (!missing(images)) params$images <- as.numeric(images)
   if (!missing(headers)) params$headers <- headers
-  if (!missing(body)) params$body <- body
-  if (!missing(http_method)) params$http_method <- http_method
-  if (!missing(save_args)) params$save_args <- save_args
-  if (!missing(load_args)) params$load_args <- load_args
+  if (!missing(body)) params$body <- jsonlite::unbox(body)
+  if (!missing(http_method)) params$http_method <- jsonlite::unbox(http_method)
+  if (!missing(save_args)) params$save_args <- jsonlite::unbox(save_args)
+  if (!missing(load_args)) params$load_args <- jsonlite::unbox(load_args)
 
   res <- httr::GET(splash_url(splash_obj), path="render.json", encode="json", query=params)
 
@@ -106,4 +109,4 @@ render_json <- function(splash_obj = splash_local, url, base_url=NULL, quality=7
 print.splash_json <- function(x, ...) {
   cat("<splashr render_json() object>")
   invisible(x)
-}
+}
\ No newline at end of file
diff --git a/R/render-png.r b/R/render-png.r
index 29572de..31b3558 100644
--- a/R/render-png.r
+++ b/R/render-png.r
@@ -1,39 +1,42 @@
 #' Return a image (in PNG format) of the javascript-rendered page.
 #'
 #' @md
-#' @param width,height Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio.
+#' @param width,height Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio. These are optional
 #' @param render_all If `TRUE` extend the viewport to include the whole webpage (possibly very tall) before rendering.
 #' @return a [magick] image object
 #' @references [Splash docs](http://splash.readthedocs.io/en/stable/index.html)
 #' @inheritParams render_html
 #' @export
 render_png <- function(
-  splash_obj = splash_local, url, base_url=NULL, width=1024, height=768,
-  timeout=30, resource_timeout, wait=0, render_all=FALSE,
+  splash_obj = splash_local, url, base_url=NULL, width, height,
+  timeout=30, resource_timeout, wait=0, render_all=TRUE,
   proxy, js, js_src, filters, allowed_domains, allowed_content_types,
-  forbidden_content_types, viewport="1024x768", images, headers, body,
+  forbidden_content_types, viewport="full", images, headers, body,
   http_method, save_args, load_args) {
 
   params <- list(url=url, timeout=timeout,
                  wait=if (render_all & wait == 0) 0.5 else wait,
-                 viewport=viewport, width=width, height=height,
+                 viewport=jsonlite::unbox(viewport),
                  render_all=as.numeric(render_all))
 
-  if (!missing(base_url)) params$base_url <- base_url
+  if (!missing(width)) params$width <- width
+  if (!missing(height)) params$height <- height
+
+  if (!missing(base_url)) params$base_url <- jsonlite::unbox(base_url)
   if (!missing(resource_timeout)) params$resource_timeout <- resource_timeout
-  if (!missing(proxy)) proxy$base_url <- proxy
-  if (!missing(js)) params$js <- js
-  if (!missing(js_src)) params$js_src <- js_src
-  if (!missing(filters)) params$filters <- filters
-  if (!missing(allowed_domains)) params$allowed_domains <- allowed_domains
-  if (!missing(allowed_content_types)) params$allowed_content_types <- allowed_content_types
-  if (!missing(forbidden_content_types)) params$forbidden_content_types <- forbidden_content_types
-  if (!missing(images)) params$images <- images
+  if (!missing(proxy)) params$proxy <- jsonlite::unbox(proxy)
+  if (!missing(js)) params$js <- jsonlite::unbox(js)
+  if (!missing(js_src)) params$js_src <- jsonlite::unbox(js_src)
+  if (!missing(filters)) params$filters <- jsonlite::unbox(filters)
+  if (!missing(allowed_domains)) params$allowed_domains <- jsonlite::unbox(allowed_domains)
+  if (!missing(allowed_content_types)) params$allowed_content_types <- jsonlite::unbox(allowed_content_types)
+  if (!missing(forbidden_content_types)) params$forbidden_content_types <- jsonlite::unbox(forbidden_content_types)
+  if (!missing(images)) params$images <- as.numeric(images)
   if (!missing(headers)) params$headers <- headers
-  if (!missing(body)) params$body <- body
-  if (!missing(http_method)) params$http_method <- http_method
-  if (!missing(save_args)) params$save_args <- save_args
-  if (!missing(load_args)) params$load_args <- load_args
+  if (!missing(body)) params$body <- jsonlite::unbox(body)
+  if (!missing(http_method)) params$http_method <- jsonlite::unbox(http_method)
+  if (!missing(save_args)) params$save_args <- jsonlite::unbox(save_args)
+  if (!missing(load_args)) params$load_args <- jsonlite::unbox(load_args)
 
   res <- httr::GET(splash_url(splash_obj), path="render.png", encode="json", query=params)
 
diff --git a/R/splashr-package.R b/R/splashr-package.R
index 468136b..6ca3a35 100644
--- a/R/splashr-package.R
+++ b/R/splashr-package.R
@@ -18,7 +18,7 @@
 #' @importFrom stringi stri_split_regex stri_split_fixed stri_detect_regex
 #' @importFrom HARtools writeHAR HARviewer renderHARviewer HARviewerOutput
 #' @importFrom xml2 read_html url_parse
-#' @importFrom jsonlite fromJSON
+#' @importFrom jsonlite fromJSON unbox
 #' @importFrom openssl base64_decode
 #' @importFrom clipr read_clip
 #' @importFrom lubridate ymd_hms
diff --git a/man/render_har.Rd b/man/render_har.Rd
index f9101f6..96c92ed 100644
--- a/man/render_har.Rd
+++ b/man/render_har.Rd
@@ -39,7 +39,7 @@ render_har(splash_obj = splash_local, url, base_url, response_body = FALSE,
 
 \item{forbidden_content_types}{Comma-separated list of forbidden content types. If present, Splash will abort any request if the response’s content type matches any of the content types in this list. Wildcards are supported.}
 
-\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is 1024x768.}
+\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is "full".}
 
 \item{images}{Whether to download images.}
 
diff --git a/man/render_html.Rd b/man/render_html.Rd
index 5e34a80..e6182e4 100644
--- a/man/render_html.Rd
+++ b/man/render_html.Rd
@@ -36,7 +36,7 @@ render_html(splash_obj = splash_local, url, base_url, timeout = 30,
 
 \item{forbidden_content_types}{Comma-separated list of forbidden content types. If present, Splash will abort any request if the response’s content type matches any of the content types in this list. Wildcards are supported.}
 
-\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is 1024x768.}
+\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is "full".}
 
 \item{images}{Whether to download images.}
 
diff --git a/man/render_jpeg.Rd b/man/render_jpeg.Rd
index 3998586..c7adf72 100644
--- a/man/render_jpeg.Rd
+++ b/man/render_jpeg.Rd
@@ -5,10 +5,10 @@
 \title{Return a image (in JPEG format) of the javascript-rendered page.}
 \usage{
 render_jpeg(splash_obj = splash_local, url, base_url = NULL, quality = 75,
-  width = 1024, height = 768, timeout = 30, resource_timeout, wait = 0,
-  render_all = FALSE, proxy, js, js_src, filters, allowed_domains,
-  allowed_content_types, forbidden_content_types, viewport = "1024x768",
-  images, headers, body, http_method, save_args, load_args)
+  width, height, timeout = 30, resource_timeout, wait = 0,
+  render_all = TRUE, proxy, js, js_src, filters, allowed_domains,
+  allowed_content_types, forbidden_content_types, viewport = "full", images,
+  headers, body, http_method, save_args, load_args)
 }
 \arguments{
 \item{splash_obj}{Object created by a call to \code{\link[=splash]{splash()}}}
@@ -19,9 +19,9 @@ render_jpeg(splash_obj = splash_local, url, base_url = NULL, quality = 75,
 
 \item{quality}{JPEG quality parameter in range from 0 to 100. Default is quality=75.}
 
-\item{width}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio.}
+\item{width}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio. These are optional}
 
-\item{height}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio.}
+\item{height}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio. These are optional}
 
 \item{timeout}{A timeout (in seconds) for the render (defaults to 30).}
 
@@ -45,7 +45,7 @@ render_jpeg(splash_obj = splash_local, url, base_url = NULL, quality = 75,
 
 \item{forbidden_content_types}{Comma-separated list of forbidden content types. If present, Splash will abort any request if the response’s content type matches any of the content types in this list. Wildcards are supported.}
 
-\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is 1024x768.}
+\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is "full".}
 
 \item{images}{Whether to download images.}
 
diff --git a/man/render_json.Rd b/man/render_json.Rd
index 0e5c3ce..33d6ecb 100644
--- a/man/render_json.Rd
+++ b/man/render_json.Rd
@@ -5,7 +5,7 @@
 \title{Return a json-encoded dictionary with information about javascript-rendered webpage.}
 \usage{
 render_json(splash_obj = splash_local, url, base_url = NULL, quality = 75,
-  width = 1024, height = 768, timeout = 30, resource_timeout, wait = 0,
+  width, height, timeout = 30, resource_timeout, wait = 0,
   render_all = FALSE, proxy, js, js_src, filters, allowed_domains,
   allowed_content_types, forbidden_content_types, viewport = "1024x768",
   images, headers, body, http_method, save_args, load_args, html = TRUE,
@@ -21,9 +21,9 @@ render_json(splash_obj = splash_local, url, base_url = NULL, quality = 75,
 
 \item{quality}{JPEG quality parameter in range from 0 to 100. Default is quality=75.}
 
-\item{width}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio.}
+\item{width}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio. These are optional}
 
-\item{height}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio.}
+\item{height}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio. These are optional}
 
 \item{timeout}{A timeout (in seconds) for the render (defaults to 30).}
 
@@ -47,7 +47,7 @@ render_json(splash_obj = splash_local, url, base_url = NULL, quality = 75,
 
 \item{forbidden_content_types}{Comma-separated list of forbidden content types. If present, Splash will abort any request if the response’s content type matches any of the content types in this list. Wildcards are supported.}
 
-\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is 1024x768.}
+\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is "full".}
 
 \item{images}{Whether to download images.}
 
diff --git a/man/render_png.Rd b/man/render_png.Rd
index 6867742..2ef513d 100644
--- a/man/render_png.Rd
+++ b/man/render_png.Rd
@@ -4,11 +4,11 @@
 \alias{render_png}
 \title{Return a image (in PNG format) of the javascript-rendered page.}
 \usage{
-render_png(splash_obj = splash_local, url, base_url = NULL, width = 1024,
-  height = 768, timeout = 30, resource_timeout, wait = 0,
-  render_all = FALSE, proxy, js, js_src, filters, allowed_domains,
-  allowed_content_types, forbidden_content_types, viewport = "1024x768",
-  images, headers, body, http_method, save_args, load_args)
+render_png(splash_obj = splash_local, url, base_url = NULL, width, height,
+  timeout = 30, resource_timeout, wait = 0, render_all = TRUE, proxy, js,
+  js_src, filters, allowed_domains, allowed_content_types,
+  forbidden_content_types, viewport = "full", images, headers, body,
+  http_method, save_args, load_args)
 }
 \arguments{
 \item{splash_obj}{Object created by a call to \code{\link[=splash]{splash()}}}
@@ -17,7 +17,7 @@ render_png(splash_obj = splash_local, url, base_url = NULL, width = 1024,
 
 \item{base_url}{The base url to render the page with.}
 
-\item{width, height}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio.}
+\item{width, height}{Resize the rendered image to the given width/height (in pixels) keeping the aspect ratio. These are optional}
 
 \item{timeout}{A timeout (in seconds) for the render (defaults to 30).}
 
@@ -41,7 +41,7 @@ render_png(splash_obj = splash_local, url, base_url = NULL, width = 1024,
 
 \item{forbidden_content_types}{Comma-separated list of forbidden content types. If present, Splash will abort any request if the response’s content type matches any of the content types in this list. Wildcards are supported.}
 
-\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is 1024x768.}
+\item{viewport}{View width and height (in pixels) of the browser viewport to render the web page. Format is “<width>x<height>”, e.g. 800x600. Default value is "full".}
 
 \item{images}{Whether to download images.}
 
diff --git a/tests/testthat/test-splash.R b/tests/testthat/test-splash.R
index 17e914d..da56fc3 100644
--- a/tests/testthat/test-splash.R
+++ b/tests/testthat/test-splash.R
@@ -1,16 +1,18 @@
 context("basic functionality")
 test_that("we can do something", {
 
+  test_url <- "http://localhost:8050/"
+
   xpct <- function(x) {
     spact <- splash_active()
     expect_that(spact, equals(TRUE))
     expect_that(length(splash_debug()), equals(7))
     expect_that(length(splash_version()), equals(9))
-    expect_that(render_json(url = "https://httpbin.org/get"), is_a("splash_json"))
-    expect_that(render_png(url = "https://httpbin.org/get"), is_a("magick-image"))
-    expect_that(render_png(url = "https://httpbin.org/get"), is_a("magick-image"))
-    expect_that(render_html(url = "https://httpbin.org/get"), is_a("xml_document"))
-    expect_that(render_har(url = "https://httpbin.org/get"), is_a("har"))
+    expect_that(render_json(url = test_url), is_a("splash_json"))
+    expect_that(render_jpeg(url = test_url), is_a("magick-image"))
+    expect_that(render_png(url = test_url), is_a("magick-image"))
+    expect_that(render_html(url = test_url), is_a("xml_document"))
+    expect_that(render_har(url = test_url), is_a("har"))
   }
 
   spact <- splash_active()