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Dear Riccardi Users & any knowledgeable Stargazers: the specs of the smaller, M63 Riccardi APO reducer say that it has a 42mm corrected field. Does it work well with full-frame cameras? I would like to use it on my 90/600 TS photoline APO. The bigger one would be quite tricky to mount:(. As for camera, 1st round I'd get a sony A7, but later on maybe a large mono CCD/CMOS when they become more affordable.

Hi everyone, really need some help as I can't get my head around this. I need a coma corrector as I'm using a Newtonian and coma is so bad so I'm getting the baader mpcc mark 3 coma corrector. I would also like to get a focal reducer of around 0.5x My question is can anyone suggest an item where these are built into one, or can a focal reducer be screwed into the coma corrector?

Hello, I own a Vixen ED-80 refractor which is used with a custom focuser by Telescope Service. (pictured below) A Celestron f/6 SCT reducer corrector did not provide decent images either because it is not appropriate or because I did not maintain the correct distance. I am thinking of buying the Sky-Watcher .85x Reducer/Flattener instead, as it is made for similar ED80 telescopes. I do not know what is the correct distance of the SkyWatcher reducer for my setup and more important, I do not know if it will focus with the custom TS focuser. Do you have any similar setup that you have used successfully? Clear Skies! Paul

Time for yet another cry for help when it comes to choosing diagonal. I have read the many similar threads and gathered some knowledge (too many to start linking). I have come some way in my process and now that it is coming to final decisions I would like to hear from the experts. Not many of threads I have read end with the OP returning to deliver some review/verdict of his/her final decision. While I wait for response on some thread where I asked about the result, the eagerness in me forces me to write my own thread. Perhaps some of the people asking these questions before can now answer in my thread as experts!I have the Nexstar Evolution 9.25 and am currently using the stock diagonal. My eyepieces are the Baader 8-24 mm zoom and the stock 40 mm Plössl. I would also like to upgrade EPs and there I'm looking at something better in 24 mm range, as well some nice low power for more FOV. I'm following threads about EPs and SCTs with great interest for this (on CN). Can say that I'm currently leaning towards the 1.25" 24 mm ES 68° and 2" 36 mm Hyperion aspheric (if going 2" route).I'm thinking 2 alternatives (including a budget alternative for one of them). I'm looking at Baader mainly for ClickLock (and expect good optics): Baader T2 Zeiss prism with a 1.25" ClickLock EP (T2 part #08) -OR- the 2" prism with 2" ClickLock (splurging that is). The budget alternative would be to get the non-Zeiss T2 prism instead for the 1.25". Worth noting that I would like to get the Celestron f/6.3 Reducer/Corrector. This would be for future purposes of delving into EAA but of course I would use it visually as well (especially if choosing the T2 route). The reasoning for my alternatives: Go for the 2" Zeiss prism to theoretically get the best of the best in visual terms. I would make better use of the 46 mm baffle tube opening. Theoretically possible to combine with the R/C thanks to relative short light path (although not necessarily needed with 2" EPs). Downside of going to 2" accessories would be the cost, EPs, filters etc., on top of diagonal. Would not be able to spend all these costs at once. Cheaper route with T2 prism (especially the non-Zeiss), not only diagonal but also the other accessories. Cost of the R/C would be comparable to e.g. the 36 mm aspheric and give similar power and FOV with the 24 mm ES, i.e. the 24 mm would act as both. Extra plus is the ClickLock clamp for 1.25" with built in fine focusing not involving the mirror. Downside of knowing that not all light coming out of baffle tube is used. To get the wide FOV (24 mm + R/C) I'm adding glass to the optical train (theoretically not a good thing). I'm leaning towards the T2 as it would be a cheaper diagonal and for EPs I would only need the 24 mm and then the reducer instead of a 30-40 mm, so saving the expense of one EP. Then I would already have the reducer for continuing into EAA. The questions I hope the experts here can help with: The old reducer vs 2" diagonal question. With R/C and the 24 mm I can get roughly the same mag and FOV as e.g. the 36 mm Hyperion (technically 38 mm vs 36 mm and 68° vs 72°). Also reading good things about the ES 68° and with R/C the EP should behave the same. Am I missing something here? The logics say that the I would lose some contrast with the R/C (not using full opening + adding elements), correct? Possibly flatter fields though (not important now, hopefully the EP threads might tell soon enough). The Zeiss vs non-Zeiss T2? Big differences? I have read a few posts on this so most to get some updated views here (have read that Baader has changed some things over the years). Using the R/C (f/6.3) with these prisms. I know f/7 is mentioned as "the limit" but also remember BillP's test where he was happy down to f/6 with the prisms (in 2014 at least). Perhaps most important: have I missed some other obvious alternative here? Maybe I have forgotten some question here but perhaps for the best as I assume those who have gotten this far are tired of reading now. Thanks for getting here though!Thanks,Viktor

I was wondering if the smaller, M63 thread Riccardi reducer is enough to light up a full-frame sensor? I have a 90/600 apo and intend to use the reducer with all kind of cameras I encounter, Sony A7, monochrome CCD, etc. I expect this piece of glassware to be a (very?) long-term tenant in my gearbox:). According to specs (42mm field diameter), it should cover the frame. Does anyone using this reducer?

Altair Astro has an inexpensive 0.8x reducer for refractors, but I had never seen any actual results with it, at least not with my SkyWatcher refractors (Evostar 80ED and Equinox 80ED), so I thought I'd get one and see. Turns out it works well with the Evostar, even giving you some advantages over the expensive matched 0.85x reducer, and it is not bad even at the corners of an APS-C sensor: So people who can't afford the SW 0.85x should perhaps consider it. It wasn't such a good match for the Equinox unfortunately. For more details and comparison with the TeleVue TRF-2008, you can read my blog post.

Hello 6" GSO RC users (mine's a TS Optics but all brands are similar) A picture is worth a thousand words. So if you have a photo of your rig with spacers etc and a DSLR attached, I'd love to see it so I know what I need to set me on the road to astrophotography. A big thank you to anyone willing to help. Tony

I have a celesctron nexstar 8SE OTA, to which I attach my focal reducer (0.63x by celestron), the a T-Adapter-SC, a t-ring and then my dslr. Does the T-Adapter affect the performance or use of the focal reducer? Emilis

Hello and welcome to my first Astro topic.. So I am new to Astronomy... I have a skymax 127 with AZ-GTi mount which I had its maiden outing this week. I'm using a basic SV205 camera fitted direct to the tube. My eventual image of the moon is below after stacking et-al.. I've gray-scaled it as the colour is just rubbish on that camera. But as you can see I'm tightly 'zoomed' in. Thing is I'd like to be able to get the whole moon in my FOV. I've seen YT vids on using reducers but I'm wondering if anyone here has done it on a 127? If so... 1 How did the image work out? 2 What's the cost of getting that to work V cost of another more suited (smaller i guess) scope?

Hi all, With the ongoing stock shortage it's going to be sometime before I get my hands on my desired scope for my ideal setup. I'd like to make the most of my current scope until stocks replenish and so I have a few questions about Flatteners and Reducers. I currently have a Celestron Inspire 100az (details here), a Canon 450D and a EQ3 Pro (synscan). As I understand, the 660mm focal length makes the scopes FOV too narrow for a mount such as the EQ3. Am I able to add a reducer to bring the focal length down to a level that would be suitable for this mount? If so, can someone provide some guidance as to which reducer would be the right choice? This brings me onto my next problem; I can achieve focus with my Canon 450D DSLR in the Celestron 100AZ but by only using the supplied diagonal (here) and my 2x Barlow (here). I have tried using the 68mm extension tube that came with the T-ring and adaptor (here), inserting this directly into the scope but cannot achieve focus at all. In addition to a reducer, what else do i need to add to the OTA to get focussed? S.

Hello, does anyone know if my imaging train looks correct, and if it does, why am i still getting these coma errors? Could it be incorrect backfocus? Searching the internet makes me think my dslr is 44mm, adding the t ring (even tried a 1mm spacer too) gets me to the required 55mm (assuming that's correct) I have no idea how to solve this and i feel like I'm just throwing money down the drain fighting this in vien. Help would be much appreciated. Skywacher Evostar 72ed Reducer rotator for 72ed (needs this for extra distance to achieve focus, the reducer and adapter alone doesn't allow for enough outwards travel) Reducer/corrector for ed72 Canon eos 650d

For my 16" Meade ACF F8, I'll be buying a Moravian G4-9000 camera with KAF-9000 chip. The KAF-9000 chip is 36.7mm square, a big chip! on paper the Explore Scientific 3" 0.7 reducer/field flattener could work well right to the edge, but has anyone tried it with Meade ACF telescopes? Also, I'm wandering what is the light cone of the Meade 16" ACF F8, will I get a lot of vignetting with that chip? I have a friend who has tried a KAF-9000 with his Meade 12" ACF F8 with very acceptable results. Thank you for your time.

Hello, I recently purchased my first telescope and camera, and now I want to make sure I have the correct Barlow or reducer to couple them together to achieve Nyquist sampling on the camera (or slight over-sampling). In case it’s important, I’m interested in planetary imaging—in theory that shouldn’t matter for this sampling question, but maybe there are other considerations to take into account. I used this calculator (https://astronomy.tools/calculators/ccd_suitability) and plugged in my info: Telescope: Celestron 8 SE Camera: ZWO ASI462MC Seeing: experimented with this one, but would like to get optics that allow for poor or very poor Binning: prefer 1x1 to preserve spatial resolution, but could consider higher if SNR is a problem I’ve seen on several forum posts that people often use a 2x Barlow to couple the two. However, according to this calculator, that will always lead to over-sampling. If anything, it says I should use no intermediate optics or even a reducer. So my questions are: Binning: Will I be able to see anything with 1x1 binning, or should I expect to need to bin to collect enough light? Is there some other consideration that’s more important here than achieving correct sampling? It seems like most others are over-sampling, and perhaps there’s a good reason for this. If so, is there another formula that would let me determine the appropriate optics to buy? Thanks in advance for any help!

Hi, sorry if this was already posted, i'm looking for a flattener/reducer for my William Optics Zenithstar 66 SD (already asked WO by email) they reply me that since this product is discontinued over 10 years ago, i need to look for FlatII, FlatIII - with 2"sct thread Flat6a with 2"SCT adapter and i saw this one https://www.firstlightoptics.com/reducersflatteners/william-optics-adjustable-flat6a-iii-08x-reducer-flattener.html and this one https://www.aliexpress.com/item/32917167365.html but i'm not very sure, so i'll ask before buying anything i will use it on my recently buyed star adventurer classic (buyed on FLO) Thanks in advance

Hi All I posted recently asking about suitability of using a 0.6 reducer with a 66mm scope....to cut a long story short I decided to get one and try it with my Megrez 72. I bought one (the Altair 0.6 reducer flattener) and it arrived yesterday ...however there are no instructions or diagrams whatsover included (not good) and I am wondering about the back focus spacing. After some searching online it seems the measurement is 55mm.....however I cant find a diagram of this exact reducer anywhere showing where to measure the distance from. I emailed the shop and they kindly replied saying they 'thought' it was from the lens of the reducer itself but not sure. Usually there is a point on the reducer like a certain shoulder to measure the distance to your camera sensor from. Does anyone have this reducer and know where to measure from? ...or a link to a diagram? Thanks in advance Tom

Hi Everyone, need a little help choosing the right flattener/reducer for the William Optics Zenithstar73. I am after one that does both jobs so that rules out the dedicated Flat73 which is just a flattener! So I was wondering if I could get away with the Flat6 0.8 reducer which does say it works on scopes 70 - 80mm f/6 but doesn't list the ZS73 in the models list or do I need to spend the extra and get the Flat6A11? Can anyone shed some light on this have email 365 where I have seen the Flat6 but had no reply. Thanks in advance.

Hi Everyone, I've just bought a Skywatcher Evostar 72ed but can't get hold of the sky-watcher .85x reducer/flattener or the OVL versions in these current times. Can anyone suggest any alternatives to the above? Many thanks John (UK)

Hi all gazers, i am having second thoughts about getting a crayford for my C9.25 (non HD) and that is because of the 0.63 Reducer / Flattener that i am imaging with. As camera i use the Nikon D7100. According to my calculations, and what i have read on internet, the optimal distance between the reducer and the chip is 105mm, the only focuser that allows for this distance (107-ish mm) is the feathertouch with the "shorty" sct-adapter witch is 56mm, my nikon T2-flange to the chip is 50mm. The Steeltrack and moonlite is far to long (93 and 91mm) But, according to some people, i can put my FR after the focuser with good performance, but how would that effect the reducing, and flattening? are there any out there who use crayfords and reducers on their SCT's with DSLR's? If nothing seems to work, i am getting the feathertouch microtouch replacement for the stock SCT-focuser. // Daniel

Well look what the postman just delivered As I'm at work and the photo booth's in my office I thought I'd send some images of my new gadget .. I meant to buy this when I bought my APM early this year but I already had the Tele Vue TRF 2008, Markus Ludes of APM said it would work a treat with the EX428 being that its got a small chip so I delayed (very true so thanks Markus) , I actually found the little 428 didn't need a flattener at all with the APM 107 combo and the F/6.5 is reasonably fast as it is. Ive now got another 314L and its similar to the 428 in taht it also doesn't need a flattener so why did I bother? Well I am going to dabble again with OSC and I have my eyes set on a QHY8L as my next camera, I just loved the OSC work flow although hated the Moon and poor seeing which really punishes Colour CCD's/CMOS's. I really am looking forward to the f/4.87 speed , its going to come in handy for both the super sensitive ATIK 314 & later the large chipped QHY8 and my 40D which I will be testing it on over the next few weeks.. This image shows the 45mm aperture which will easily cover a DSLR chip... At over half a kilo its no flyweight

This is the first such image from my Mewlon. As most may know I have struggled to use the Mewlon from my location, since it need excellent skys to get the most from it. However, I have spent a lot on this telescope and definately want to get more use under my skys with it, therefore, back in October 2012 I modified it with the new corrector baffle system designed to eliminate coma. The Mewlon is a Dall-kirham cassegain telescope and these have the best on axis optical performance; however, they do have off-axis coma inherrent in their design. The corrector baffle solves this issue and lowers the effective focal length, which is what I was interested in! With the baffle in place the focal ratio drops from F12 to F10, not much change there? But with the new focal reducer it drops to F7, just a little below 2m focal length and thats the change that I was looking for. This image of the Bubble is taken a F7 using the Mewlon. The coditions were average (Seeing & Transparency) and yet I was able to use the Mewlon!!! Its not all be pain sailing, I have also had to learn to drift align on the pole. To do this I use Metaguide since its also used to confirm that the collimation of the Mewlon is spot on. Metaguide is actually able to measure the drift and report back the new value after your adjustments, so you know very quickly if you are going in the wrong direction, which is great. Anyway the image capture was as follows; Red 8x300sec Blue 8x300sec Green 8x300sec Lum 8x300sec HA 10x600sec So about 4.5hours in total, probably I need another night to get the most from the image? Another important point is at the moment I cannot flat field the Mewlon, I need to build a light box!!! This would also improve the image quality eventually. I hope you like it? I'm very pleased with the results.

Hi, wow ive had more data in a week than the last year! Here is my take of the famous Triplet.. Thanks to a top stacking tip from Olly and Rob Ince.. 28 Lum 600 second 1x1 20 Red 300 second 2x2 20 Green 300 second 2x2 20 Blue 300 second 2x2 Stacked in Astroart , tweaked in Pixinsight & Photoshop..