From 361536cbb5562b0adac452f5e7d5e24b8a277042 Mon Sep 17 00:00:00 2001 From: Jeremy Likness Date: Sun, 23 Nov 2025 09:28:03 -0800 Subject: [PATCH 1/7] add redirect --- Gemfile.lock | 26 ++- _layouts/redirect.html | 29 ++++ ...4-01-05-william-optics-redcat-71-review.md | 157 +----------------- 3 files changed, 44 insertions(+), 168 deletions(-) create mode 100644 _layouts/redirect.html diff --git a/Gemfile.lock b/Gemfile.lock index cf09da5..77fa5b5 100644 --- a/Gemfile.lock +++ b/Gemfile.lock @@ -3,7 +3,7 @@ GEM specs: addressable (2.8.7) public_suffix (>= 2.0.2, < 7.0) - bigdecimal (3.1.9) + bigdecimal (3.3.1) colorator (1.1.0) concurrent-ruby (1.3.5) em-websocket (0.5.3) @@ -14,7 +14,10 @@ GEM fastimage (2.4.0) ffi (1.17.2) forwardable-extended (2.6.0) - google-protobuf (4.30.2) + google-protobuf (4.33.1) + bigdecimal + rake (>= 13) + google-protobuf (4.33.1-x64-mingw-ucrt) bigdecimal rake (>= 13) http_parser.rb (0.8.0) @@ -66,26 +69,21 @@ GEM pathutil (0.16.2) forwardable-extended (~> 2.6) public_suffix (6.0.2) - rake (13.2.1) + rake (13.3.1) rb-fsevent (0.11.2) rb-inotify (0.11.1) ffi (~> 1.0) - rexml (3.4.1) - rouge (4.5.2) + rexml (3.4.4) + rouge (4.6.1) safe_yaml (1.0.5) - sass-embedded (1.88.0) - google-protobuf (~> 4.30) + sass-embedded (1.94.2) + google-protobuf (~> 4.31) rake (>= 13) - sass-embedded (1.88.0-x64-mingw-ucrt) - google-protobuf (~> 4.30) + sass-embedded (1.94.2-x64-mingw-ucrt) + google-protobuf (~> 4.31) terminal-table (3.0.2) unicode-display_width (>= 1.1.1, < 3) - tzinfo (2.0.6) - concurrent-ruby (~> 1.0) - tzinfo-data (1.2025.2) - tzinfo (>= 1.0.0) unicode-display_width (2.6.0) - wdm (0.1.1) webrick (1.9.1) PLATFORMS diff --git a/_layouts/redirect.html b/_layouts/redirect.html new file mode 100644 index 0000000..5679a6d --- /dev/null +++ b/_layouts/redirect.html @@ -0,0 +1,29 @@ +--- +layout: null +--- + + + + + + Page Moved + + + + + + +

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+ + \ No newline at end of file diff --git a/_posts/2024-01-05-william-optics-redcat-71-review.md b/_posts/2024-01-05-william-optics-redcat-71-review.md index 7e27483..973532e 100644 --- a/_posts/2024-01-05-william-optics-redcat-71-review.md +++ b/_posts/2024-01-05-william-optics-redcat-71-review.md @@ -1,159 +1,8 @@ --- -layout: post +layout: redirect title: "Review: William Optics Redcat 71 My new favorite lens" author: deepskyworkflows -categories: [ Review ] -tags: [ moon, "IC431", "IC432", "IC434", "Flame Nebula", "Orion B", "IC435", "NGC2023", "NGC2024", M45 ] -toc: true +redirect_to: https://www.dswgalleries.com/post/review-william-optics-redcat-71-my-new-favorite-lens image: assets/images/2024-01-05/redcat71review.jpg description: "A complete review of the William Optics Redcat 71 astrograph refractor telescope, with comparisons to the Svbony SV503 70ED." -featured: true -hide: true -comments: true ---- - -After over three years of practicing this hobby, I finally decided to expand my equipment and take my imaging to the next level. A colleague of mine at Microsoft recently invested in a new rig and offered to sell his existing hardware at a pretty nice discount. I picked up the new telescope as part of a package deal and definitely paid less than the $1800 USD retail. If I purchased one new, I'd pick it up from [High Point Scientific](/external?t=https://www.highpointscientific.com/william-optics-redcat-71-f-4-9-apo-imaging-astrograph-with-wifd). - -{% include blogimage.html url="redcat2.jpg" description="The William Optics Redcat 71." half=false target=true %} - -## Svbony SV503 70ED comparison - -The question I'm asked most often is, "How does this compare to your existing [Svbony SV503 70ED](/svbony-sv503-review) telescope?" To save you the trouble of additional searching, here is a breakdown of key differences I noticed and my thoughts/comments: - -|**Feature**|**SV503 70ED**|**Redcat 71**|**Notes**| -|--|--|--|--| -|Aperture|70mm|71mm| | -|Focal Length|420mm|348mm| | -|F-stop|f/6|f/5|The field of view/speed is very similar between the pair.| -|Retail|~$400|~$1700|At over 4 times the cost, is the Redcat worth the additional investment of $1300?| -|Length|12.52"|16.81"|The Redcat is bulkier and less portable.| -|Weight|4.9#|7.1#|The SV503 works easily with standard tripods and even portable mounts like the [Star Adventurer Mini](/camera-astrophotography-with-tracking-hardware). The Redcat requires something sturdier like the ZWO AM5.| -|Design|S-FPL-51 2-element achromatic doublet|FPL-53 4-element Petzval apochromatic doublet|The Redcat 71 uses superior glass and provides a much cleaner, clearer image without chromatic aberration.| -|Dew shield|Built-in|Built-in|| -|Focus|Dual-speed toothed focuser|Helical or WFID|Both focusers provide fine controls with locking mechanisms. It was easier for me to install an electronic auto-focuser on the Redcat due to the design.| -|Stars|Stretched at the edge, halos|Round to the edge, no halos|The superior optics of the Redcat really shine when it comes to stars. The SV503 requires a field flattener/reducer to provide pinpoint stars to the edge.| -|Backfocus difficulty|Hard|Easy|The SV503 requires precise backfocus or stars _will_ get distorted. The Redcat, on the other hand, only requires you to _find_ focus. If you are able to space your sensor so you are able to focus it, the stars will be round throughout the field of view. -|Chromatic aberration|Significant|Minimal|My consistent issue with the SV503 is blue/purple halos around stars that I don't get with the Redcat.| -|Final thoughts|This is a fantastic scope and probably the best option I am aware of at its price point. With the addition of a flat field will produce remarkable images.|The fact this telescope was designed for astrophotography is evident in the quality of the images it produces. The ease of backfocus, star shape and lack of halos or significant chromatic aberration make this worth every dollar of investment.|If your budget can afford it, I recommend the Redcat. The SV503, on the other hand, is far less expensive, more portable and easier to use on traditional tripods and portable mounts.| - -OK, now that I've shared the comparisons, let's dig into the details. - -## The Specs - -> 📝 **NOTE** I use Amazon affiliate links and may receive a commission for purchases you make after following the links. The commission helps me pay for the software and equipment necessary for astrophotography and to produce the content for Deep Sky Workflows. I also link to places like [High Point Scientific](/external?t=https://www.highpointscientific.com/), [B & H Photo](/external?t=https://www.bhphotovideo.com/), and [Woodland Hills Telescopes](/external?t=https://telescopes.net). These are all vendors I've had great experiences with but am not affiliated with in any way. - -The Redcat 71 comes with a nice, wide field of view at 348mm focal length. The 71mm aperture makes it f/5, a decent speed for deep sky photography. The design does not require a reducer or flattener, and with my [2.5x TeleVue PowerMate](/external?t=https://amzn.to/467u83b) increases to 870mm. - -Here is what the field of view using a [ZWO ASI294MC Pro](/external?t=https://amzn.to/3ScBE7a) and a [Sony A7R IV camera](/external?t=https://amzn.to/4bQq0Wo) with the Redcat 71 pointed at M42: the Great Orion Nebula. - -{% include blogimage.html url="astronomy_tools_fov.png" description="Field of view of William Optics Redcat 71 with ZWO ASI294MC Pro and Sony A7R IV" half=false target=true %} - -The Redcat with a 2.5x Barlow-style lens has the perfect field of view for photographing the moon. - -{% include blogimage.html url="astronomy_tools_fov2.png" description="The William Optics Redcat 71 field of view with a Barlow-style lens field of view" half=false target=true %} - -Here's a photograph I took with a similar (only 2x) configuration: - -{% include blogimage.html url="/assets/images/gallery/cloudy-moon-newport/cloudy-moon-newport.jpg" -description="A cloudy moon in Newport shot with William Optics Redcat 71" half=true target=true %} - -The Redcat is a Petzval refractor. This means it incorporates extra lenses between the objective lens and the focuser. The result is a much flatter field, less need for precise backfocus spacing, and an image that is star halo-free with minimal chromatic aberrations. The apochromatic (a lens with superior correction of spherical and chromatic aberrations compared to achromatic lenses) doublet refractor uses extremely high quality FPL-53 glass. - -> Field of view images courtesy of [Astronomy tools](/external?t=https://astronomy.tools). - -Let's checkout what comes in the box! - -## What's in the box - -Although I purchased my Redcat 71 secondhand, the owner did a great job of retaining all of the parts and manuals. The standard package includes: - -- The **348mm focal length telescope** (of course) -- A **threaded dust cap** made of sturdy metal that fits M48 threads -- A **tilt adapter** to correct for issues in your imaging train -- A built-in **field rotator** so you can rotate your camera angle to frame your target -- A **saddle handlebar** with M4 thumb screws you can use to add a guide scope -- The **helical focuser** (standard version) or proprietary WIFD focuser -- A **focuser tension ring** to lock in focus when you achieve it -- A **focuser gear ring** you can use with a belt to attach an auto-focuser -- **Arca Swiss/Vixen Plate** to easily attach to most mounts -- **Mounting Rings** -- A built-in **dew shield** to reduce condensation on the lens -- A **Bahtinov mask** to assist with achieving focus -- A **carrying bag** to transport the unit -- No need for a **field flattener** because of the design - -It's a very solid offering and I found I had all the elements I needed to integrate it with my own system. - -## What's not in the box - -Honestly, _nothing_. The box had everything I needed. - -## Things I wish I knew - -I really wasn't surprised by much with this scope, other than just how great the quality is. It is heavier and bulkier than the Svbony, but still very portable. I've taken it with me on several occasions to the beach to zoom in on waves, ships, and whales. - -## Results - -I've had the opportunity to shoot a variety of targets with the Redcat so far. Here are some examples. First, let's take a look at star quality. This is a single raw, uncropped and unedited (except for stretching the brightness levels to make it visible) 5-minute exposure. - -{% include blogimage.html url="rawredcat.jpg" description="The William Optics Redcat 71 image quality." half=false target=true %} - -Here is the upper left corner, zoomed in to show stars near the edge. - -{% include blogimage.html url="rawedge.jpg" description="The William Optics Redcat 71 pinpoint stars at the edge." half=false target=true %} - -Now let's see how this integrates into a final result! - -### Nebulae - -My favorite nebulae shots were all taken with the Redcat. It has the perfect field of view for most popular targets. Here is Orion's belt, featuring the star Alnitak, the Flame Nebula, and the Horsehead Nebula. - -{% include blogimage.html url="/assets/images/gallery/da-belt/da-belt.jpg" -description="Orion's belt shot with William Optics Redcat 71" half=true target=true %} - -See all of my [William Optics Redcat 71 nebulae photographs](/gallery/?telescope=William%20Optics%20Redcat%2071&category=Nebula). - -### Clusters - -The optics make capturing clusters a breeze with pinpoint stars. This was the first time I was able to fully appreciate the delicate dust surrounding the M45: Pleiades cluster. - -{% include blogimage.html url="/assets/images/gallery/dust/dust.jpg" -description="M45 Seven Sisters with William Optics Redcat 71" half=true target=true %} - -See all of my [William Optics Redcat 71 cluster photographs](/gallery/?telescope=William%20Optics%20Redcat%2071&category=Cluster). - -### The Moon - -I'm excited to see what is possible when photographing the moon with scope. My favorite image so far is this capture of a crescent moon with earthshine. - -{% include blogimage.html url="/assets/images/gallery/crescent-earthshine/crescent-earthshine.jpg" -description="The moon with William Optics Redcat 71" half=true target=true %} - -You can view all my [published astrographs taken with the William Optics Redcat 71](/gallery/?telescope=William%20Optics%20Redcat%2071) to date. - -## Pros and Cons - -The pros: - -1. No pulling out hair in frustration trying to achieve perfect backfocus distance -1. Beautiful stars -1. Minimal chromatic aberration -1. Superior image quality -1. Sturdy design -1. Easy to mount and accessorize -1. Built-in field rotator -1. Built-in dew shield -1. Built-in focus tension ring -1. Great for both lunar and deep sky observations - -The cons: - -1. Almost $2k price tag -1. Too heavy for basic tripods and mounts -1. I wanted to have at last three cons, but can't think of a third - -I'd love to hear _your_ thoughts in the comments! - -## Conclusion - -My only regret with my purchase of the Redcat 71 is that I didn't buy one sooner. That is a compliment for the SV503 for its performance at a ~$400 price point. The Redcat optics combined with a high resolution camera and narrowband filters is opening new doors and possibilities for my imaging sessions. I'm creating my favorite images in over three years of practicing this hobby. A month ago, I would have declared this as my main scope for all full-disk lunar and deep sky observations in 2024. However, there is a twist: I just received my HyperStar for my Celestron EdgeHD 9.25" SCT and have not yet had the opportunity to test how that will impact my imaging plans in the coming year. \ No newline at end of file +--- \ No newline at end of file From 38fbfb9c6fa115b1ad9867ab58ad5c2f7eee624a Mon Sep 17 00:00:00 2001 From: Deep Sky Workflows Date: Thu, 27 Nov 2025 08:00:45 -0800 Subject: [PATCH 2/7] Update Gemfile add ruby version --- Gemfile | 1 + 1 file changed, 1 insertion(+) diff --git a/Gemfile b/Gemfile index ff81ffe..c969e35 100644 --- a/Gemfile +++ b/Gemfile @@ -1,3 +1,4 @@ +ruby "3.1.2" source "https://rubygems.org" # Hello! This is where you manage which Jekyll version is used to run. # When you want to use a different version, change it below, save the From db3e0f7c6245276aecc56ca0b0402cb10c2ad06e Mon Sep 17 00:00:00 2001 From: DeepSkyWorkflows Date: Thu, 27 Nov 2025 09:21:03 -0800 Subject: [PATCH 3/7] Ruby version. --- .ruby-version | 1 + Gemfile | 2 +- Gemfile.lock | 2 +- 3 files changed, 3 insertions(+), 2 deletions(-) create mode 100644 .ruby-version diff --git a/.ruby-version b/.ruby-version new file mode 100644 index 0000000..81f1b89 --- /dev/null +++ b/.ruby-version @@ -0,0 +1 @@ +3.4.7 \ No newline at end of file diff --git a/Gemfile b/Gemfile index c969e35..d59e723 100644 --- a/Gemfile +++ b/Gemfile @@ -1,4 +1,4 @@ -ruby "3.1.2" +ruby "3.4.7" source "https://rubygems.org" # Hello! This is where you manage which Jekyll version is used to run. # When you want to use a different version, change it below, save the diff --git a/Gemfile.lock b/Gemfile.lock index 77fa5b5..db8e512 100644 --- a/Gemfile.lock +++ b/Gemfile.lock @@ -107,4 +107,4 @@ DEPENDENCIES webrick BUNDLED WITH - 2.3.4 + 2.7.2 \ No newline at end of file From 6019dfab273d454e4ac0b4adc2aabe54633dfafe Mon Sep 17 00:00:00 2001 From: Deep Sky Workflows Date: Thu, 27 Nov 2025 09:25:30 -0800 Subject: [PATCH 4/7] Update Gemfile ruby version --- Gemfile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Gemfile b/Gemfile index c969e35..d59e723 100644 --- a/Gemfile +++ b/Gemfile @@ -1,4 +1,4 @@ -ruby "3.1.2" +ruby "3.4.7" source "https://rubygems.org" # Hello! This is where you manage which Jekyll version is used to run. # When you want to use a different version, change it below, save the From d1c2604e5a0be846fcfbf80dbfe4476efcc7f74c Mon Sep 17 00:00:00 2001 From: Deep Sky Workflows Date: Thu, 27 Nov 2025 09:26:05 -0800 Subject: [PATCH 5/7] Update Gemfile.lock bundle version --- Gemfile.lock | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Gemfile.lock b/Gemfile.lock index 77fa5b5..c1fa04c 100644 --- a/Gemfile.lock +++ b/Gemfile.lock @@ -107,4 +107,4 @@ DEPENDENCIES webrick BUNDLED WITH - 2.3.4 + 2.7.2 From 5cdf6b3b5fdcd322dfa4878594d2306160c5e62f Mon Sep 17 00:00:00 2001 From: DeepSkyWorkflows Date: Thu, 27 Nov 2025 10:54:29 -0800 Subject: [PATCH 6/7] CSV for build --- Gemfile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Gemfile b/Gemfile index d59e723..aaa1160 100644 --- a/Gemfile +++ b/Gemfile @@ -9,7 +9,7 @@ source "https://rubygems.org" # This will help ensure the proper Jekyll version is running. # Happy Jekylling! gem "jekyll", "~> 4.3.3" - +gem "csv" # This is the default theme for new Jekyll sites. You may change this to anything you like. gem "minima", "~> 2.5" From aeeb3aadbb33c99e5a2500920084217c79c6af33 Mon Sep 17 00:00:00 2001 From: DeepSkyWorkflows Date: Thu, 27 Nov 2025 11:02:05 -0800 Subject: [PATCH 7/7] logger and base64 for build --- Gemfile | 2 ++ 1 file changed, 2 insertions(+) diff --git a/Gemfile b/Gemfile index aaa1160..fe88083 100644 --- a/Gemfile +++ b/Gemfile @@ -10,6 +10,8 @@ source "https://rubygems.org" # Happy Jekylling! gem "jekyll", "~> 4.3.3" gem "csv" +gem "logger" +gem "base64" # This is the default theme for new Jekyll sites. You may change this to anything you like. gem "minima", "~> 2.5"