Can't decide.. Mono + filters or OSC "and" Mono!

[Sp@ce_d]

Been thinking about this to the point of going around in circles!

I've been planning on a dual imaging setup for a while now (been using a dual frac setup, swapping camera between them depending on FOV requirements) but rather than get another dslr I'm wanting to take the leap from modded dslr to ccd, but I'm having a bit of trouble planning my roadmap.

Looking at a budget of say ~2000 I could get either:

A: 314L+, EFW2 filterwheel and filters (LRGB and Narrowband)

or

B: 314L+ Mono and a 314L+ OSC

Option B seems as if it would get me to my dual imaging setup in one foul swoop, so is there really a big difference by going down the 2 mono cam route?

[ncjunk]

I would go option A and use the dslr as the second cam. Or possibly option B with an ha filter for the mono for when the moons around.

I prefer the mono and filter wheel and filters as it gives you more options. Then in the future be on the lookout for a second hand osc bargain.

I'm not a big fan of osc cameras.

[steppenwolf]

I use both OSC and mono + filters ccd cameras on my dual imaging system. In truth, I made use of what I already had available with regard to cameras but it has worked out very well as I have plenty of flexibility. I'd go for option 1 with a full set of narrowband filters, use your DSLR for the time being and save up for a OSC ccd camera.

[Sp@ce_d]

Ok.. Thanks for the replies Neil, Steve. You both seem to favour the way I was originally planning this.. supplementing the DSLR with a mono CCD (plan A).

However, the more I think about that plan the more confused I seem to get trying to decide which CCD will complement the DSLR to give me satisfactory results. If I'm trying to double the amount of data collected on a single target then am I not limited to choosing a CCD that matches up sensor size & FOV with that of the DSLR? Which starts looking rather expensive for a first toe in the water of CCD imaging!

So that's how I started thinking about getting two CCD's the same size. Plus I already have a 2" Ha filter I use with the DSLR so that would give me Ha collection with the mono whilst collecting RGB all in one go with the OSC CCD ( ok I know it's not exactly the same as RGB.. but surely close?)

Of course another advantage with having a smaller sensor/larger pixel CCD than the DSLR would be reaching targets that are just too small to bother with on the DSLR sensor.

[ncjunk]

Ok.. Thanks for the replies Neil, Steve. You both seem to favour the way I was originally planning this.. supplementing the DSLR with a mono CCD (plan A).

However, the more I think about that plan the more confused I seem to get trying to decide which CCD will complement the DSLR to give me satisfactory results. If I'm trying to double the amount of data collected on a single target then am I not limited to choosing a CCD that matches up sensor size & FOV with that of the DSLR? Which starts looking rather expensive for a first toe in the water of CCD imaging!

So that's how I started thinking about getting two CCD's the same size. Plus I already have a 2" Ha filter I use with the DSLR so that would give me Ha collection with the mono whilst collecting RGB all in one go with the OSC CCD ( ok I know it's not exactly the same as RGB.. but surely close?)

Of course another advantage with having a smaller sensor/larger pixel CCD than the DSLR would be reaching targets that are just too small to bother with on the DSLR sensor.

It depends on the scopes you are going to use with each CCD. You don´t have to match the CCDs. I could use

my OSC which is 6meg pixels at 4.5 pixel size on a similar scope to my 285 based CCD which has 7.8 pixel size.

Yes I would not be using all of the pixels on the OSC but I could use the HA or Luminance from the Mono together

with the colour from the OSC. This means I have a large format sensor for widefield if I want it.

It´s about matching the focal length to the CCD against the size of object you are trying to image. I can use my

C11 with M51 at 1800 FL and it fits perfectly on the sensor or I could get widefield on the OSC and the ED80.

If use the OSC on the C11 I´ll have to crop it as the stars towards the edge get distorted.

My point is that you could quiet happily use a large sensor with a 314 CCD and mix and match or gather twice the

data or switch to widefield. I think it gives you more options.

check with steve on how to combine the subs from two different sized CCDs but I understand it isn´t a problem.

I am planning to do that early next year and use my 285 ccd with the large format qhy8l. Just need to figure out

what scopes I want to use with each CCD.

[Sp@ce_d]

It depends on the scopes you are going to use with each CCD. You don´t have to match the CCDs. I could use

my OSC which is 6meg pixels at 4.5 pixel size on a similar scope to my 285 based CCD which has 7.8 pixel size.

Yes I would not be using all of the pixels on the OSC but I could use the HA or Luminance from the Mono together

with the colour from the OSC. This means I have a large format sensor for widefield if I want it.

It´s about matching the focal length to the CCD against the size of object you are trying to image. I can use my

C11 with M51 at 1800 FL and it fits perfectly on the sensor or I could get widefield on the OSC and the ED80.

If use the OSC on the C11 I´ll have to crop it as the stars towards the edge get distorted.

My point is that you could quiet happily use a large sensor with a 314 CCD and mix and match or gather twice the

data or switch to widefield. I think it gives you more options.

check with steve on how to combine the subs from two different sized CCDs but I understand it isn´t a problem.

I am planning to do that early next year and use my 285 ccd with the large format qhy8l. Just need to figure out

what scopes I want to use with each CCD.

I'm currently using an 80ED & WOZS66 (flat/red on 80ed & reducer on the wo) I was thinking of getting another 80ED for a true matched dual setup. But from what you're saying a smaller sensor CCD on the WO might work with the DSLR on the 80ED. I've been trying out David Campbells FOV calculator (http://www.12dstring.me.uk/fov.htm) with various combinations until I'm blue in the face to be honest & I guess I'm at the point where I've given myself a phobia of making a costly mistake. So I guess it would be nice to know of a similar setup that's already working for somebody else.

Meantime.. it seems I should decide on which mono CCD with a set of narrowband filters. Plus I have to consider the learning curve of being new to CCD imaging. If it's possible to use the 1000D data with a 314L then I'm still inclined to go for the Atik as a first CCD.

Thinking about this, I do have Registar which I believe might be useful for this kind of thing, although I havn't really used it much as I failed to get too much success with it on a small mosaic I gave up on from last year.

[ncjunk]

Check with steppenwolf on how he does his and you could borrow some 314 subs off of someone and try some processing.

I'd be inclined to have a practise with someone elses data to make sure its ok for you and how you want to work.

[ollypenrice]

The trouble with DSLR colour is that it isn't very good, notably on stars. It can be OK on other targets though.

I have OSC and mono CCD. I like the OSC because I can end up running around like a madman with three rigs on the go and OSC gives me a break. However, I have the same dilemma as you as I approach the possibility of going up to full frame. The mono is sorted. That won't be mine and is on its way. But do I buy an OSC to run parallel with it or a full frame mono? Yikes, very difficult. OSC is not always that great on some targets. Harry Page and I both find it thin on galaxies, for instance.

Honestly a tough call but in any event at least one of the cameras needs to be a mono CCD to get the NB data. Mono NB and OSC do generally work well together. I've done a fair few pictures that way but more on nebulaie than galaxies, it must be said. My own jury is still out.

Olly

[Sp@ce_d]

The trouble with DSLR colour is that it isn't very good, notably on stars. It can be OK on other targets though.

I have OSC and mono CCD. I like the OSC because I can end up running around like a madman with three rigs on the go and OSC gives me a break. However, I have the same dilemma as you as I approach the possibility of going up to full frame. The mono is sorted. That won't be mine and is on its way. But do I buy an OSC to run parallel with it or a full frame mono? Yikes, very difficult. OSC is not always that great on some targets. Harry Page and I both find it thin on galaxies, for instance.

Honestly a tough call but in any event at least one of the cameras needs to be a mono CCD to get the NB data. Mono NB and OSC do generally work well together. I've done a fair few pictures that way but more on nebulaie than galaxies, it must be said. My own jury is still out.

Olly

Ah that's interesting Olly.. I don't feel so bad now knowing it's not just all in my head worrying whether to go OSC

I know you use Registar.. would you say it was capable of handling data from such differing sized sensors as I'm considering if I go for mixing the data from my DSLR & a 314L for instance?

Graham..

[steppenwolf]

check with steve on how to combine the subs from two different sized CCDs but I understand it isn´t a problem.

Registar should be able to do this although I use two star align in MaximDL and it works just fine. With regard to mismatches in data sets, I routinely combine images taken with a Megrez 72D, 0.8x focal reducer and SXV-H9 mono CCD with those taken with an FLT 98 and SXVF-M25C OSC CCD. - obviously, the finished image size and resolution is set by the Megrez/H9 combination.