New scope recommendations - Forums

Topic starter

Jul 8, 2023

Hi all,

About a year ago I upgraded my mount to a EQ35M. I have an altair astro 294C, a ZWO guide cam and a 200 mm guide scope. I'm really happy with all of this but I've started to find it hard to motivate myself to get out and take photos even though now I can get exposure times of

0 minutes now.

I think it's because I'm still using my Skywatcher 130 PDS and I've used it for the majority of targets that fit nicely in the FOV. I've wanted a greater zoom for a while and think its time to upgrade from my starter scope.

What would you guys suggest? I can't go above £700 really.

andrea tasselli

Frequent contributor

Jul 8, 2023

Get a 6" f/4 newton.

matt113d

Topic starter

Jul 8, 2023 · Edited: Jul 8, 2023

Thank you for the recommendation. However, I said in the original post I'm looking to go to a longer focal length than 650mm.

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dkamen

Jul 8, 2023

You can't. Not with the eqm35.

matt113d

Topic starter

Jul 8, 2023 · Edited: Jul 8, 2023

Are you sure? I think that's unlikely. I'm not talking about a 2 m SC here. Just looking for suggestions.

EDIT. You have pictures on your profile taken with longer focal lengths on this exact mount?

Brian Puhl

IOTD Staff

Jul 8, 2023

I've seen folks use a 6" newt on an EQM-35 and produce decent results, but it took him alot of tuning and tweaking… I'd recommend against it.

130PDS is about as big as I'd go on that mount. If you like the 294C, you could consider getting a 294M (used) where Bin1 is unlocked and sample the skies alot better. Going from 4.63um pixels to 2.3um pixels means you'll sample at 0.73 arc seconds instead of 1.4 arc second. I believe you'd be oversampling your dawes limit on that scope, but it should give you more detail.

beyond that, if you wanna go bigger, you should really get a better mount first.

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DanRossi

Jul 9, 2023 · Edited: Jul 9, 2023

I've seen folks use a 6" newt on an EQM-35 and produce decent results, but it took him alot of tuning and tweaking... I'd recommend against it.

130PDS is about as big as I'd go on that mount. If you like the 294C, you could consider getting a 294M (used) where Bin1 is unlocked and sample the skies alot better. Going from 4.63um pixels to 2.3um pixels means you'll sample at 0.73 arc seconds instead of 1.4 arc second. I believe you'd be oversampling your dawes limit on that scope, but it should give you more detail.

beyond that, if you wanna go bigger, you should really get a better mount first.

I agree. I have a GSO newtonian 6" F/6 at 900mm, and I pair it with an EQ6-R. Any smaller mount would probably be a exercise in frustration due to the weight of the OTA & photography equipment, and also the focal length.

dkamen

Jul 9, 2023

Are you sure? I think that's unlikely. I'm not talking about a 2 m SC here. Just looking for suggestions.

EDIT. You have pictures on your profile taken with longer focal lengths on this exact mount?

Yes, with a VMC110L which is 1050mm, but reduced to about 700mm effective using a focal reducer, and binned 2x2, and more than half the subs failing unless conditions were extremely favourable and tuning (which I was doing constantly) extremely precise and the target bright enough to use much shorter exposures than I would have liked.

Rafael Amarins

Jul 9, 2023 · Edited: Jul 9, 2023

I would say you're probably optimized in terms of scope and mount.
What you could do to improve your resolution/pixel scale is moving from 294MC to 533 or even consider the new Player One Uranus C Cooled.
If you want more details the alternative would be getting smalller pixels.
I'm currently using a IMX294 and considering the new Player One Uranus C cooled for the same reasons you are: more details, better resolution, tight pixel scale.

Joe Linington

Jul 9, 2023

I have an EQM-35 and you are going to have a hard time getting any better than your current setup. I have the 294m with the 2.3 um pixels attached to a 102mm scope (571mm focal length) and my EQM simply can’t guide reliably below 1 arc second (usually between 1-1.2 arc seconds). I have to run that combo on my heavier EQ6R to get my guiding below the sampling. You could certainly buy a 183 or 294m to get better resolution but I promise you will then want a bigger, more accurate mount.

You might be able to run a 90mm mak or a C5 SCT but you would take a huge hit on f/ratio and imaging time and still likely have guiding issues.

I wish it was better news. Maybe you should consider a wider view like a 60-76mm refractor scope.

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