Astrophysics 1100GTO V's EQ6Pro

[batema (Mark)]

Hi,

Today I reached my goal of saving for an Astrophysics 1100 GTO but would like to know if I had my William Optics Flt 110 with a focal length 770mm and F7 image the same object such as M 42 on the EQ6Pro and then the AP1100GTO for the same time and conditions would I see a difference in the image????? Also where would its strengths lie?

Thank you

Mark

[RickS (Rick)]

Mark,

If you're imaging at 770mm FL then I reckon either would probably do a decent job. I'm not personally familiar with the EQ6Pro but they seem OK, maybe with some tweaking required.

If you ever intend to use a heavier scope and/or longer FL then the A-P mount will just eat it up and the EQ6Pro will probably cause you grief (one option to fix this may be an AO unit).

I'd go for the AP1100 in a heartbeat. I prefer to spend the extra money to get good results quickly without pain and suffering but some people are masochists

Cheers,
Rick.

[g__day (Matthew)]

Mark,

The example you just gave was too simple a task for either mount if set up well.

But if you were to point a 14" SCT at the Crab nebulae for a few hours then you would probably begin to understand what the quality of the mount gives you when hard targets come in to play.

The AP is also giving you unswerving reliability, night after night. I don't think I have ever hear anyone complain about there's not being up to scratch - ever!

Pick the right tool for the job you are envisaging; if its simple - fair enough, if over time it is likely to be challenging - why even consider a lesser mount when it the heart of your system?

Matthew

[h0ughy (David)]

Mark - i would love the goal you have just reached - awesome. but for something in the middle what about a eq8 - save some pennys for a CCD?

But dont listen to me - that 1100 is sure pretty!!

[DJT (David)]

I went from a HEQ5 to an AP900, the precursor to the AP1100. The mount just melts away into the background and if you setup your scope right and your PA is good it just does its thing without a murmur. Your limiting factor as Matthew says then becomes what you are using for guiding...Thats what has an impact on what your images look like, oh yes, plus processing..plus camera...plus optics. But your start point, the AP, wont be the problem.

Check the various sites for what the capacities are for the 2 models. Both will deal with what you have now. Its then just a case of what you want to do in the future. After all, if you can save for that mount, that wont be the end...

[gregbradley]

Eggy stars are eggy stars at any focal length. It just means you tend to "get away with" worse tracking at shorter focal length. 770mm is starting to get into medium focal length and eggy stars will show up in your images.

I am not saying EQ6 gives eggy stars - I know a lot use them and their are many fine images. But I bet they had to tweak their mounts to achieve that.

Whereas with the AP mount once setup it will give round stars routinely and you can concentrate on other aspects of imaging. Without a good mount you tend to spend more time trying to get round stars and sometimes you win and sometimes you don't.

Do you notice it in an image? Yes. Eggy stars also means the object of interest is also blurred/smeared. So you lose sharpness, detail. A well tracked image with a nice scope should have a certain crispness to it.
Microcontrast, fine detail and overly pleasing sharp and crisp look to the image is impossible without good tracking.

Additionally it would be much much harder if you wanted to do longer exposures like say 20 to 30 minutes for less noisy narrowband images like Ha, O111 and S11.

In short until you can achieve round stars routinely in your setup you haven't even reached the bus stop yet let alone got on the bus!

An AP 1100 would be a dream mount and I believe AP preload PEC into their mounts as well right? That's a big plus too. It also has a powerful capacity so if later on you want to image with a larger scope (noone here ever upgrades their gear to larger, bigger and better do they??) then your mount is ready to go without that having to be the upgrade first.

Greg.

[batema (Mark)]

Thank you all.

[LewisM]

Mark,

I image with a 900mm (f/9) focal length, or reduce it to f/6.3. I use a Vixen GPD2, and with a precise polar alignment, I get perfect stars and impeccable guiding. Below is a crop of a SINGLE 20 minute exposure, zoomed 700%. This was RIGHT before the flip.

Maybe not PERFECT stars, but seem fine to me. Do 10 min subs or even 5, and it will be even better

This was using an FL102S with an archaically heavy SBIG ST-8XE (weighs more than a DSLR ) Total on mount weight is around 9.5 kg. The GPD2's IMAGING max is 10 kg It still eats it.

If you can afford an AP, then go for it, but if you want to get a mount near as capable for your smaller scope that delivers superb tracking, reliabilty and quality, then MAYBE consider the GPD2.

Recently, I got clouded over during a run, but could see an end to the cloud. I left it running. PHD bleeped and flashed for 7 minutes - solid white on the guider image. When the cloud cleared, the guidestar was still DIRECTLY under the crosshairs, and PHD instantly relocked onto it. I have also left it running "visually" untouched - 37 minutes and the star was still in the centre of the reticle crosshairs - probably could have gone longer.