10 min subs with budget setup. Is this alright?

[Quatermass]

Hi Pix you have the same modded system I have got and your guiding looks spot on just a light pollution filter needed it looks like. My controller burned out after leaving it in the rain silly me but have now got a replacement and just need some clear skies. To be honest I have not done much guiding on the Galaxy's that I have been imaging I'm saving that for the Nebula season.

[Gina]

Oh no Gina, that was a guided one but with a budget setup: EQ5 + SW200P with the hand controller modded to send pulses to the mount via PHD.

Ah right Seemed far too good to be true Anyway your setup is working really well

[pixueto]

Hi Pix you have the same modded system I have got and your guiding looks spot on just a light pollution filter needed it looks like. My controller burned out after leaving it in the rain silly me but have now got a replacement and just need some clear skies. To be honest I have not done much guiding on the Galaxy's that I have been imaging I'm saving that for the Nebula season.

I’m glad you got a replacement QM. That SW handset doesn’t look very robust but hey that’s one of the things that make it easier to mod.

Yes, I did notice that you haven’t done much guiding since you modded your kit. I suppose that your new ED80 is taking up all your time now . By the way, your EQ5 conversion proyect thread and the boredom resulting from a string of bad weather is what got me into all this. Before that, I was contented with 1’minute unguided subs !!!

[Quatermass]

Well its kept you busy thats for sure we have had so many cloudy nights in suffolk any imaging was off the cards yet alone guiding. I have to say I dont like guiding very much it works but takes much longer to set up and so I will only do it if I really have to. Most night I am happy to do lots of short subs as normal. That will change later on I know but most nights Im content with short subs if I can get away with it.

Sent from my GT-S5670 using Tapatalk 2

[Gina]

I was deprived of guiding tonight so only managed 2m subs before the stars started trailing. Still, at least I managed to get 50 0f them after much faffing about trying to find gremlins in the system!

[pixueto]

you've done very well with that setup, I'm sure many people would have said it can't be done with a 200p on an EQ5. Tracking looks great, just a bit of coma, easily fixed with a Baader coma corrector (which work fantastic by the way). Just take more and more subs. The 350d is actually very low noise, compared to the more recent Canons (low megapixel). ISO800 is more like ISO400 on the later cams.

Have you got a photo of your setup? It would be useful for others to see what can be done with that combination.

Well, this is my setup for whoever may be interested:

-SW200P on EQ5 with modded handset (shoestring mod)

-Stellavue F50 finder + 2X celestron ultima barlow to reach focus + Philips SPC 880 flashed (I use this setup as the guiding scope)

-canon 350D (unmodded) + a very cheap chinese remote shutter timer

-aurora flat panel (for taking flat frames)

-Zoostorm notebook (probably the cheapest notebook out there) to control the mount through PHD

-Bahtinov mask to reach focus

-extension lead

And yes...the grass needs cutting!

[Jessun]

That's a very good start! Try sigma stacking so that you can keep more subs. A few trails are not enough reason to throw a sub in the bin. Also with a DSLR in particular try dithering. That helps randomize the noise a great deal.

As to LP, filter or no filter... Tricky one, and almost comes down to personal preference. I don't use a filter, and I'm in a city centre. I find that if you let the stacking software normalize colour balance then the glow is no big deal. I had a play with an IDASv4 LP filter, which is supposed to be good but I pretty much immediately put it back in the box. The subs were too dark and the target was barely visible.

I wonder though if imaging 'slow' - I'm at f8 sadly... - means that a filter does more damage than good, but going faster could reverse this. Just a very vague theory.

As to sub length - experiment! :-)

[laser_jock99]

I reckon I'd try an LP filter and 5 min subs. I did a comparison using my skywatcher LP filter and without it a while back.

Just foind the pics again now

This is a 10 min sub of M31 without an LP filter.

and this is the addition of a skywatcher 2" LP filter taken directly after, same length sub 10 mins on M31.

Thats's a huge difference might invest in one of those for my urban trips.

[pixueto]

Well, I got the Astronomik CLS filter. Next clear night I'll give it a try. Now what worries me is getting the correct white balance. Has anyone any experience with this? Just when you think you are getting on top of things, something new comes up that you have to contend with!

[badgers]

Again pix, I'm well impressed with your 10min subs on that setup.

My budget guided setup wouldn't go above 5 minutes without serious guiding issues. I had to upgrade to a HEQ5 Pro to get over 10 minutes.

I use a Baader UHC filter for contrast and light pollution as I shoot from a balcony right in the centre of an urban environment, worked a treat for me.

This is a raw 10 min ISO800 light frame of M51 from a heavy LP area with the Baader UHC.

Coma is less of an issue for me on the 150P as long as I get the target fairly central, but I definitely will get the MPCC soon.

Also a before/after shot on M45 attached, shots taken only 30 minutes apart but with the UHC and without.

But again, nice work on the guiding, that's the difficult bit sorted.

[Gina]

That's a great light sub - stack some of those and you'll do very well

[pixueto]

Again pix, I'm well impressed with your 10min subs on that setup.

My budget guided setup wouldn't go above 5 minutes without serious guiding issues. I had to upgrade to a HEQ5 Pro to get over 10 minutes.

I use a Baader UHC filter for contrast and light pollution as I shoot from a balcony right in the centre of an urban environment, worked a treat for me.

This is a raw 10 min ISO800 light frame of M51 from a heavy LP area with the Baader UHC.

Coma is less of an issue for me on the 150P as long as I get the target fairly central, but I definitely will get that soon.

Also a before/after shot on M45 attached, shots taken only 30 minutes apart but with the UHC and without.

But again, nice work on the guiding, that's the difficult bit sorted.

Thank you badgers. You got us all green with envy since you got that HEQ5 pro. I keep saying to mysel that I can't afford it but I find myself spending over £100 a month on astronomy equipment! Last month it was the Aurora panel, now is the Astronomik CLS filter. My wife isn't happy so I feel under pressure to produce some nice pictures and impress her. funnily enough she must think the smaller the item, the cheaper and that LP filter came in an envelope -I just need to make sure I hide the receipt! Well, at least my 5 year old son is still very much into astronomy.

I can't believe how much difference your LP filter can make! Is that M51 single shot unprocessed? I cannot get such detail even after stacking several subs!

What about the white balance? How do you correct the colour if it gets shifted by your filter?

[badgers]

Thank you badgers. You got us all green with envy since you got that HEQ5 pro.

My mount upgrade was due to defeat, at not being able to get beyond 5 min subs on the EQ3-2.

If I'd managed to get guiding going like you or QM have, I'd probably have splurged the money on a 2nd hand ATIK camera instead : )

[pixueto]

I suppose I am lucky in that the weather is kind to me in my area as windy nights are rare. I took those subs on a very still night. Maybe that's the secret to get 10min subs with the EQ5. I would imagine that if you live in, say Scotland, you are going to need a much solid mount.

[pixueto]

it looks really good but also shows be of coma, try added a baader MPCC to the optical train for a flatter image then fine tune from there. But other then that you are off to a good start.

Can you attach the Baader MPCC to your camera and telescope using the SkyWatcher direct SLR connection?

[ultranova]

I think you are well on the way to some great shots like the other have already said, just a couple more bits of equipment to

make it much easier to get ridd of that nasty looking light pollution, and some kind of field flattner and you will be there,

Hope you dont mind , i had a little go with your pic in PI

Paul

[pixueto]

I think you are well on the way to some great shots like the other have already said, just a couple more bits of equipment to

make it much easier to get ridd of that nasty looking light pollution, and some kind of field flattner and you will be there,

Hope you dont mind , i had a little go with your pic in PI

Paul

Thank you very much.

I have got now a nastronomik LP clip filter. Do I need a coma corrector/field flatner? Couldn't that be solved with photoshop?

[ultranova]

The clip filter will help you allot, as far as i know (some one please tell me if im wrong)

you can sort out minor star trails in PS or in a program called star rounder but i dont beleave

you can get ridd of the stars pulling in at the edges, (coma) if there is a pice of software out there that does that i would like to know about it.

I have attached a pic showing my slr with the mppc , i think you can see my cls clip filter at the back of it the whole lot slides into the 2 inch focuser

it is a nice straight forward pice of kit, and it does a good job on flattening the field.

[pixueto]

The clip filter will help you allot, as far as i know (some one please tell me if im wrong)

you can sort out minor star trails in PS or in a program called star rounder but i dont beleave

you can get ridd of the stars pulling in at the edges, (coma) if there is a pice of software out there that does that i would like to know about it.

I have attached a pic showing my slr with the mppc , i think you can see my cls clip filter at the back of it the whole lot slides into the 2 inch focuser

it is a nice straight forward pice of kit, and it does a good job on flattening the field.

I use SkyWatcher direc DSLR connection. Will I be able to use a coma corrector/flattner with that connection?

[ultranova]

I am not sure what that connection is like so i can not comment, i would imagine that some one will know.

[nytecam]

Thanks for your feedback. There you go, a 5min and a 10 min sub as you requested.

Yep - that LP looks very familiar via my old D300 and why I don't use it for DSOs or anything much

Can someone who uses both DSLR and astro-CCDs if both cams have the same sensitivity or does one need a longer exposure on DSOs to get similar results? Of course astro-CCDs don't have ISO settings and presumely work at 'top speed' all the time. I get the impression DSLRs are hobbled

[Luis Campos]

Hello,

With that LP, you sure have a good image, the guiding looks great for an EQ5, well done!

Just one tip, lower your ISO value for 400 or even 200 ISO and go for a bit longer subs, 5 min. it's ok for an f/5 system, with the LP filter you can go a bit more say 8 min. or so depending on sky conditions. Using lower ISO improves dinamic range, this means that you can deal better with light polluted skyes, it might look that you have little data on you subs but in the final stacked and processed image is a diferent story, also the noise will be very reduced using a good set of darks matching the capture temperature or very close to it. If you can go also for a coma corrector like a Baader MPCC, it's makes a huge difference on star shapes near the edge.

Cheers,

[ultranova]

Hi, slr's are not necessarily hobbled, its just they are doing something that they were not made for, where as a dedicated ccd astro camera has been specifically designed to do the job of catching photons.

The slr was designed to be used in the sub second range ie 125 of a second on average, and it does this very well.

that's one of the reasons the astro ccd camera is cooled to help stop noise building up on the chip due to the electronics - thermal noise.

but even a one shot colour astro camera will suffer light pollution problems.

this is not so evident when using a mono camera especially when shooting with a HA filter on.

Both cameras have the goods and bads all depending on how you look at it, with the SLR having more bads due to noise problems but for the most part this can be overcome with darks, flats, etc.

Is taking astro photos with a SLR easy - hell no

Is it a cheaper way to getting into astrophotography - absolutely yes.

For the most part sky pollution can be taken out with software, it can be taken out with hardware - filters, its not ideal but if its the only way you can get the astro photos you desire you end up having not much choice.

Is a dedicated astro ccd camera more sensitive, well that is a big can of worms, what I will say is like for like on a single sub, the dedicated astro ccd camera will produce a much cleaner signal to gain ratio, but in general there probably would not be allot in it.

there are so many variables to take into account, like how high you have the gain on a SLR (iso setting) is the dedicated astro ccd camera a one shot colour or are filters used are you binning in 1x or 4 x mode on the astro ccd camera the list will go on for a while.

I am sure I will provoke more questions than answers and there is no easy way of defining what is better, obviously the dedicated ccd astro camera will do the job better with less noise, but then again I don't see many people taking photos of there family with a dedicated astro ccd camera at -20, LOL I have seen some outstanding shots taken with the Humble Slr camera, I would say in some circumstances as good as a dedicated astro ccd camera, can this quality be as often obtained as a dedicated astro ccd camera, I would have to say no, but then again people are pushing the limits of the SLR to achieve a shot that can be produced allot easyer with the dedicated astro ccd camera.

Paul.

[Gina]

Undoutedly the astro CCD camera is THE camera for the job but to get a camera with the sensor size and resolution of a DSLR costs several thousand pounds. That is why some of us are experimenting with cooling a DSLR.

[jezhughes]

that's great work with what you have!

I suffer from heavy LP too, you've done great to come out with that image, especially minus a LP filter.

I normally only get 2-3 mins on my NEQ6, but i've got a slightly bulkier heavy scope. a lot of it's luck and getting the alignment snap on, and even the mount levelling. i've re aligned 7 times in one night before trying to get tracking dead on.

anyway, well done!