Thoughts on the 50ED and ASI120MM bundle

[Jonny_H]

Hi all,

I hope everybody is doing well.

I haven't posted on here for a while as I have been tied up with work, house renovation amongst other things.

However I wanted to get everyone's views on the 50ED and ASI120MM bundle and whether it is a good 'starter' guide scope/camera.  This will be going on my SW 150PDS and HEQ5 Pro.

I wanted a relatively decent starter that will serve me well until I get even deeper in to this hobby ultimately leaving me to find trousers with deeper pockets! 🤑

anyhow- I just wanted to get everybody's thoughts.

 

Regards,

Jon

Edited January 28, 2021 by Jonny_H

[Gerr]

Hi, the Evoguide 50ED and ZWO ASI120MM bundle have worked great for my set-up. I use them to guide my ED80 refractor and SW200p reflector on a HEQ5 pro mount. Using PHD2 I get Total RMS error of about 0.6" on the refractor which allows for 10 minute plus exposures. The SW200p I only use when there is no wind (so rarely) but your 150PDS should be fine  (being smaller and lighter). When I have used the 200p I still managed 3 - 4 minute exposures without any star trailing. 

It is also a light weight option for guiding and will happily sit in the finderscope shoe of your scope.

Gerr.

[AstroExploring]

I recently started using this bundle myself and have nothing bad to say about it. It’s a great little bundle and I’ve managed to successfully guide with it no problem. I use it with a Sky-Watcher 72ED and HEQ5. 
I have a couple of YouTube videos about it in my channel if you wanted to check them out. My channel name is Astroexploring. 
 

Nick

[alacant]

On 27/01/2021 at 09:42, Jonny_H said:

50ED and ASI120MM bundle

Hi

It seems an awful lot to pay for a guiding setup when this (we can recommend the 60mm version from hands on) and this (likewise) would do the job just as well.

BTW, both items can be shipped from Europe.

Cheers

[pete_l]

22 minutes ago, alacant said:

when this (we can recommend

Or even a few €€€€s cheaper from other vendors 😉

[Seelive]

I've used the Evoguide 50ED with the ZWO ASI120MM for the past 1 1/2 years and have been happy with the guiding results I get. I set them both up on the first clear night, focused and set the supplied stop ring on the camera and also marked the camera orientation with an indelible pen mark on the camera and guidescope. I then performed a calibration run in PHD2. I now just attach the camera to the scope up to the stop ring ensuring the correct orientation and I've never had the need to refocus or recalibrate PHD2 ever since.

[alacant]

2 hours ago, pete_l said:

few €€€€s cheaper from other vendors

But be aware that those do not have European warehouses and will take longer to ship.

[ElwoodBlues]

I would recommend it.

I bought the package for guiding my sct and recently they introduced the dedicated field fleld flattener so now I'm using it has a widefield image rig and I'm very happy with it.

You could say a cheap version of a redcat setup.

[Jonny_H]

Thanks all for your responses.

For those that are using the 50ED/120MM set-up - May I also ask what main imaging camera(s) you are using...just out of curiosity. E.g. are you using Astro-modified/unmodified DSLR etc...?

 

Thanks,

Jon

[vineyard]

I use an ASI294MC Pro as the main imaging camera (and use an ASI120MMmini as the guidecam in the 50ED).  Would echo others re the widefield w the flattener - its 2 scopes in 1

[Seelive]

14 hours ago, Jonny_H said:

Thanks all for your responses.

For those that are using the 50ED/120MM set-up - May I also ask what main imaging camera(s) you are using...just out of curiosity. E.g. are you using Astro-modified/unmodified DSLR etc...?

 

Thanks,

Jon

I use an unmodified DSLR.

[Mr Thingy]

I use the SW 50ED + 120MM mini on my SW 72ED + ZWO 183 GT (with 0.8 focal reducer).

I've read before that the guide scope/cam should have a sample rate no more than 3 to 4 times that of the imaging scope/cam. 

In my case the guide has a sample rate of 3.2"/pixel, the imager 1.3"/pixel, so within the limit.

Here's a tool to calculate:

The blurb is interesting but scroll to the bottom to find the calculator.

https://astronomy.tools/calculators/ccd_suitability

Based on the above, so long as the pixel size on your DSLR is not less than 3 or 4 micron, then this guidescope/cam should be OK on a 150pds. A focal reducer would work to favour the situation and give a little more leeway.

HTH

Edited January 30, 2021 by Mr Thingy

[rnobleeddy]

I'm sure this would work. If it's just for use as a guide scope then I'd certainly consider it overkill - it's unlikely it'll guide any better than a much cheaper guide scope.  If you have other uses for it, then it's a probably a good multi-purpose OTA.

[SteveNickolls]

Just make sure your guiding software or device is compatible with the guiding camera you are to use.

Cheers,

Steve

[Jonny_H]

Thanks all for your responses.

On 29/01/2021 at 17:21, vineyard said:

I use an ASI294MC Pro as the main imaging camera (and use an ASI120MMmini as the guidecam in the 50ED).  Would echo others re the widefield w the flattener - its 2 scopes in 1

Perhaps for another topic but I am also in two minds between the 294MC Pro and the 533MC Pro - stepping up to a cooled imaging camera configuration. Currently using an old 400d slr unmodified.

I think I am more swayed towards the 533. In terms of stats and figures- both seem to be within the recommended ranges when coupled with a SW 150pds. 

20 hours ago, rnobleeddy said:

I'm sure this would work. If it's just for use as a guide scope then I'd certainly consider it overkill - it's unlikely it'll guide any better than a much cheaper guide scope.  If you have other uses for it, then it's a probably a good multi-purpose OTA.

Agreed using solely for a guide scope is probably considered as overkill but as Vineyard mentioned i will also use it as an independent scope also.

I now need to do some serious thinking 🙂

[The Lazy Astronomer]

On 31/01/2021 at 09:24, Jonny_H said:

Agreed using solely for a guide scope is probably considered as overkill but as Vineyard mentioned i will also use it as an independent scope also.

I now need to do some serious thinking 🙂

I can highly recommend it as an imaging scope in its own right and the possibility of duel purpose use was exactly why I bought it (in fact it's outside right now taking widefield shots of M81, M82, and a couple of their other very small, very faint friends).

The only complaint about it is that it suffers from some bloating in the blue and luminance channel* - managed to correct that with the Astronomik L3 filter and am now very pleased with the results. 

 

*I use a mono camera, so I think it was caused by my filters passing unfocused UV, not sure if it would be an issue with a colour camera.

 

[masjstovel]

I got the setup you're mentioning. I got the 50ED for better pixel scale (3.2"/pixel). It's fantastic. Built in helical focuser is a dream, even if its a little "steel against steel" feel on it. 

(A mess with the cables, but its not set up for imaging here. It looks like a mess then too, but still..)

[Jonny_H]

13 minutes ago, masjstovel said:

I got the setup you're mentioning. I got the 50ED for better pixel scale (3.2"/pixel). It's fantastic. Built in helical focuser is a dream, even if its a little "steel against steel" feel on it. 

(A mess with the cables, but its not set up for imaging here. It looks like a mess then too, but still..)

Thanks masjstovel. I ended up pushing the button on this last week - it arrived yesterday. I have trial tested the set-up indoors as I had reservations about fixing the 50ed via the finderscope shoe (I haven't received the unc bolts yet to fix a dovetail to the top of the tube rings). On that note - did you have issues unscrewing the stock unc bolt (the one with the black knurled wheel screwed onto it)? Assuming of course that you replaced that with your own unc bolts?  Or did you keep that - screw the dovetail on and secure with a cap etc...?

 

Edited February 6, 2021 by Jonny_H

[masjstovel]

@Jonny_H I replaced it with a dovetail i had. I dont remember any problems with unscrewing things no! Dont remember if i changed bolts - I think i did! 

Edit: Yeah as you can see theres 2 different bolts on the dovetail, And i use a 3D-printed clamp for best possible stability. Never really liked those adjustment-screws on the tube-rings (On any products). The clamp is attached by 2 bolts on the dovetail as well

Edited February 6, 2021 by masjstovel

[Jonny_H]

12 hours ago, masjstovel said:

@Jonny_H I replaced it with a dovetail i had. I dont remember any problems with unscrewing things no! Dont remember if i changed bolts - I think i did! 

Edit: Yeah as you can see theres 2 different bolts on the dovetail, And i use a 3D-printed clamp for best possible stability. Never really liked those adjustment-screws on the tube-rings (On any products). The clamp is attached by 2 bolts on the dovetail as well

Thanks for your reply.

Re: the bolts that attach the clamp to the dovetail - did you use the existing screw holes on the dovetail (and tailored your clamp holes to match)? Assuming the bolts you used are the same/similar UNC 1/4 1 inch bolts?

Sorry for all the questions - it seems that you cannot simply plug and play fit the guidescope to the OTA so searching for inspiration!

[masjstovel]

Oh, I see.
The clamp i have were 3D-printed to fit the existing holes yes. Its an identical dovetail from SW as the one thats on the bottom that was in the 150PDS package. 
 

[Jonny_H]

59 minutes ago, masjstovel said:

Oh, I see.
The clamp i have were 3D-printed to fit the existing holes yes. Its an identical dovetail from SW as the one thats on the bottom that was in the 150PDS package. 
 

I have, for the time being just used the dovetail which came with the 50ed. It doesn't reach to both sides of the OTA tube rings but seems very secure. 

I have some bolts coming in the post next week so I will probably switch to the other dovetail. It will be more secure but more importantly it should centralise the 50ed more than current set-up. See pic below.

 

[masjstovel]

I eventually understood what you meant, my bad:)

The attachment holes underneath the supplied dovetail with the 50 ED, i dont know if they fit the "Medium Dovetail 21cm" which is the one supplied with the 150PDS. 

[Jonny_H]

OK - so the block that comes with the 50ed which mounts the tube rings onto the 50ed dovetail plate - does fit to the spare 150pds OTA dovetail plate. You just have to smooth out the two middle UNC bolt holes and remove the thread. You can then pass the bolts through the dovetail so that they bite into the block. I just haven't received my bolts yet but will post a pic once done!

Edited February 8, 2021 by Jonny_H