Imaging main scope & mount, budget ~£3K

[NickK]

Well the meridian flip sounds like poorly written software! (I have a software engineering degree and over 13 years of software development experience)

James, from FLO, has clarified that the SW website is wrong. It doesn't help that they've also renamed models, leaving the product naming convention is really messed up. I'll be going for the SynTrek as, according to James, it has RA & DEC motors.

The mount will be attached to the mac and driven through AOSX.

[angusb1]

Congratulations Nick, you've made an excellent choice there. What camera do you plan to use?

[NickK]

Congratulations Nick, you've made an excellent choice there. What camera do you plan to use?

The plan is to progressively add things as I go. Currently I have an ATIK 16ic, however as I go this will be moved to guiding duties eventually.

There's going to be a little gap between the EQ6ST and the next phase. This is (a) down to end date of my contract/employment state and ( I want experience with the additional kit get get a better feel for what I'm looking for.

The cameras will probably have changed by then a little but the general expectation is to go for a large sensor mono with small pixels. The pentax should handle that easily - even with a filter wheel hung off it.

Do off-axis guiders, allow you to do away with the guide scope completely? I can see some areas having difficult lock-ons so being able to RA track a star a few arcseconds behind could be beneficial. However part of the next phase is to learn more by experience

[ollypenrice]

OAGs don't get as much light as separate guidescopes and so don't always have stars available. At your focal length and with no risk of mirror flop I would say a separate ED80 (this time the bank manager will like me...) would be far simpler on all counts. Use the 16ic and you have the demon autoguide setup. I use this pairing on both imaging mounts. Very reliable, touch wood, and I have never, ever, had to move in search of a guide star. If you have to rotate the camera you can't re-use your last lot of flats. Pain!

Small pixels? Why? This is not daytime photography. I feel sampling rate is over rated as a priority. My Atik 4000s are not for sale! Okay, I would like an 8300 chip for my camera lens imaging.

Olly

[brianb]

I feel sampling rate is over rated as a priority.

Well it helps if you can get a reasonable sampling rate (say 8 frames/sec) over a small window for focusing. But there is a good reason for not having a fast readout - with conventional CCDs, the faster you try to read them, the more noise you get from the electronics. (Given that we're talking DSO imaging here, not webcamming planets where a high frame rate is +/- essential!)

[ollypenrice]

Sorry Brian, I was talking about arcses per pixel.

Olly

[brianb]

I was talking about arcses per pixel.

Yeah ... high resolution achieved with small pixel sensors needs longer exposure than with a larger scope at the same aperture but the same image with larger pixels because signal to noise depends on the number of photons captured, and you get less photons with smaller pixels.

[narrowbandpaul]

my friend has recently acquired the iEQ45 from Altair astro.

We have yet to try it, but it promises much. Maybe worth a look at. I dont know if anyone on here has this mount.

as for OTA's, it is very difficult to get a compromise between visual and imaging.

and one that is is master of neither. I would think about what you really wannt to do and then go for it. If you want a scope for the other pursuit then that can be purchased laters if need be.

for imaging a fast newt <f5 with coma corrector, refractor with focal reducer/field flattener works well.

i would stick to a focal length of 1000mm or less...less demanding on guiding and mount and seeing conditions.

what camera is to be used for imaging?

paul

[NickK]

what camera is to be used for imaging?

Initially only the 16ic running with short subs due to the EQ6 doing the tracking. Obviously there's a big difference between the pentax and the 16ic.. however..

Then I'll look at getting a new main imaging camera and moving the 16ic to guide scope duties. I'll use a CCD calc but I'm guessing this will be somewhere around 7um pixel size.

For now - the scope and mount are going to keep me busy enough (regardless of which camera!).

[ollypenrice]

I have an IEQ45 on test but it had a problem and a new part is on its way. I look forward to trying it. It is very attractive in compactness, certainly.

Olly

[NickK]

Ok, I have ordered the following from FLO:

* EQ6 SynScan - the reason for the scan rather than the trek is this has dual saddles and the Pentax came with a losmandy wide and to be honest I'd prefer it on that than the thinner vixen. I can use the vixen saddle for the A80Mf. A saddle would have cost 25+VAT+shipping from another company... also if I have to, I can then just use the handset.. + powerlead

* EQDIR - mainly as I can use that rather than faf if I endup using ASCOM initially in a Windows Bootcamp. I'll also add support for it in AOSX.

* Baader Hyperon 13mm because it will complement my Vixen's EPs and give a wider field with the Pentax.

I think that 17Ah is a little small, so I'll find a 40 or 100Ah. It may not have the torch/radio/siren etc.. but it would last longer in the field. The only thing is I may have to find a way to increase the batterylife of the MBP (4.5 hours on a battery).

I have an AC power supply that will drive it anyway.

Thus ends my budget..

[ollypenrice]

...and begins a great deal of fun with an absolutely top class setup.

Olly

[Rossco72]

I'm not bitter in any way.....

Good luck with the setup Nick, hope it brings you lots of satisfaction.

Cheers

[NickK]

I'm not bitter in any way.....

Good luck with the setup Nick, hope it brings you lots of satisfaction.

Thank you, I was concerned that you'd gone quiet and I'd upset you. I hope that's not the case - I thank you for providing guidance and helpful critique through the discussion.

On a slightly different note.. the company in cambridge is interested in interviewing me so the temptation for the next phase earlier may grow exponentially

[NickK]

Received the EQ6 SynScan today - think I need to go to the gym!

The wide head takes the Losmandy mounting plate. With a single weight on I can achieve balance for the Pentax without a problem. I was careful with the screws (ie the ones that bend) but I can see an order to reassure my mind on those (along with a foam box for the mount).

I notice that the mount has two modes of alignment - illuminated polar mount (illumination can be varied by the controller) and 1/2/3 star alignment.

The mount does sound like it needs little lube in the gears but both axis work nicely without any grinding or other noises. The GOTO is just grin inducing - the sound the mount makes is like having your own observatory whir up

Having not had a motorised mount (manual only) previously it's interesting the noise it makes, I take it there's no park for the mount to make it completely quiet.

The overall package is very very stable. One thing that really made me grin is that the mount's control protocol is in the rear of the manual

Tomorrow is supposedly cloudy/clear.. so I hope that applies to the hours of darkness too.