R.I.P. Nikon D3100 - AstroPhotography

[squeaky]

Thanks for all that Keith.

Yes - I am NOW very much aware that I would have been better off with an EQ6 mount, so I've got one on my wish list.

I did buy a shutter remote and while it didn't make any difference that I could see to camera shake it has certainly made life easier when doing multiple exposures. The M13 I posted was from a set of 10 second subs at 3,200 and was my trial run. My first main run I did at 30 seconds and ISO 1600 and still got "mud". Better mud - but mud all the same. Shot 80 subs in Manual mode with white balance on auto and exposure compensation at zero. I'm not sure that I can go longer on my dob - so I might have to go to silly ISO's too.

The camera will save RAW and JPG at the same time so I did that to cover myself - so I have a set of each, and for sure the RAW's look better even before processing.

Time and time again I found loads of help for Canon and not a lot for the Nikon. Which is exactly why I managed, as you guys are now telling me, to get so many things wrong. And when it comes down to it - most of them aren't to do with the camera - but then - who knew? Not me. Not the camera shop. Not the help I could(n't) find on google.

If this thread ever hits the charts in google it is going to turn out to be THE most helpful thread there is for Nikons

[Mr Spock]

You wouldn't get me to part with my D300 for anything. I still have my D70 too

[squeaky]

Actually - if a mod could kindly add " - Astro Photography" to the title it might help others to find it.

[squeaky]

The answer came back on this "chipping"...

The USA version has a minii chip and adapter ring installed

to make them compatable with UK PAL video systems.I will try

to send you a link on here for a Hong Kong UK trading company

that supply a lot of UK stores they are reliable and i have used

them without any problems.Make sure you get Canon eos 550d

and not Canon REBEL T2i whitch is the USA brand.I will close now

to find the link and post it in the next message.

Regards Alan.

[Rihard]

It's a pity, as the Nikon sensors have a good Signal to Noise ratio at high iso. I haven't experienced any issues attaching and focussing my D3100 to the 200P, I didn't even add a Barlow lens (well, I did for magnification)

[squeaky]

It's a pity, as the Nikon sensors have a good Signal to Noise ratio at high iso. I haven't experienced any issues attaching and focussing my D3100 to the 200P, I didn't even add a Barlow lens (well, I did for magnification)

Then you are a very lucky bunny

Mine is the new "Gone back to black" version which is physically slightly different to the previous version. And you're on an equatorial mount which makes balancing and tracking easier.

My focal length is 1500mm at F4.9

Yours?

[squeaky]

Another penny just dropped...

When I took my trial shots of M13 they were 10 secs at ISO 3,200

So when I went for my 80 subs at 30 secs each I reduced the ISO to 1600

Given that, as it turns out, my originals were under exposed - largely because I was effectively on a high magnification with a reduced FOV and so less light intake - what I SHOULD have done for those 30 sec subs was to leave the ISO at 3,200 or even try going up to 6,400

Would that be right?

[jgs001]

Perhaps, that's another one that's hard to answer... you're looking for the ISO that gives the lowest readout noise (I think)... the number of photons incident on the sensor doesn't vary with the ISO, all that does is increase the amplification of the signal and noise... now... maybe on that camera, upping to 3200 would give acceptable results, my camera only goes to 1600, and it works best for Astro between 400 and 800. You really need to remove the barlow, you are limited by using an AltAz mount to 30 to 60 seconds generally, you might manage 2 minutes low in the east or west, if your drives are up to it, therefore running at f/10 (or thereabouts) is your biggest problem. At f/5 on an AltAz mount, with an unmodded SLR I was able to capture the bubble nebula (Ha) with 130 subs...

[squeaky]

Yes, I haven't been too happy being forced to use a Barlow. Every possible option I could find, most of which appear to work with a Canon, didn't work. The trick of moving the flex tube closer to the primary may have done - but it's too late now.

One to remember though!

[jgs001]

You actually get a bit more than 2x by using a barlow... the distance between the barlow lens cell and an ep will give you 2x, with an SLR, as the sensor sits further back, you get about 2.5x, which is actually even worse, both for the FOV and the focal ratio.

It may be that 2mm difference in the sensor plane register (that was mentioned earlier) makes the difference...

Just noticed your request to amend the title... tis done.

[Dave]

Oh! Your poor little D3100.

My Nikon's do a fantastic job.

Oh well, one man's meat and all that.

[Rihard]

Then you are a very lucky bunny

Mine is the new "Gone back to black" version which is physically slightly different to the previous version. And you're on an equatorial mount which makes balancing and tracking easier.

My focal length is 1500mm at F4.9

Yours?

Alright, I didn't know about the 2 versions of the camera. Mine is black, but was bough over 1 year ago so I guess it's the previous one.

My scope is 1000mm, F/5, and I've heard people struggling even with this one to get focus with different cameras, while as a complete beginner I just screwed the T-Ring into the scope's camera connection Et Voila, I was able to focus and take pics at the first attempt.

Good luck with the search of the right equipment. Have you thought about a dedicated CCD Imager?

Clear Skies.

[nytecam]

I bought my scope from a shop that sold both scopes and cameras, so naturally I asked them for a recommendation for a camera specifically for astro-photography. They said the Nikon D3100, and who was I to argue?...................Two hours later I was in the shop handing over the Nikon for a full refund. No arguments - think I made my case.So... guess who's shopping around for a Canon 550D ?

Well Richard - that's the saddest intro into AP and hope your new cam, whatever it is, behaves itself so you can centre objects etc. My own approach to new toys is to test in daylight to find out how it works especially lining up the finder and maybe shifting the primary mirror/new low profile focuser so prime focus can be reached without barlows. Must admit I've yet to find a telescope/cam shop that knew anything about astro or AP. Good luck in your future AP

[squeaky]

I hadn't thought of it as sad at all. It's been quite a learning experience though, and it is still quite possible that with a great deal more perseverance and experimentation I could have got good results from the Nikon.

But that's the thing. I was feeling like a pioneer opening up new ground, going where no man had gone before because there was so little advice available. And I just plain don't have the knowledge or experience to do that. I don't suppose that there will be quite as many 550 owners out there as there are 1100 owners, but that basic knowledge base should get me close to good results quite quickly and THEN I can experiment and tweak to get the best out of things.

This thread, I hope, will encourage other Nikon owners to try the suggestions made here, rather than give up with it as I did. Maybe they'll give up anyway, but at least they've got some information to work with. There's more helpful information and advice in this one thread than I managed to accumulate by scouring the web for hours, not to mention hours and hours of practical testing in daylight before ever I got a night sky to try on, and goodness knows how many phone calls and emails to the shop and other people they advised me to contact. I know we haven't had a lot of viewing nights since mid April - but that doesn't mean I wasn't hard at work learning what I could in preparation for next time... and it's not as if I expected this to be "point and shoot" stuff either; I knew it was going to be a "suck it and see" sort of thing.

Anyway... me and AP, Round II, starts next Tuesday

[squeaky]

You know I said my camera would be arriving on Tuesday?

Well, it won't be.

'Cos it's already here! yay!

Took it out, popped it into the scope - looked down the street ( a whole hundred yards so too close to be sensible) a-a-and... FOCUS!

Prime Focus gone and got without a Barlow. Just needed to use the short EP holder.

Barlows all tested - that's the Celestron standard 2x, the Meade 2x short focal length, the cheapy 3x Barlow, and the x5 Powermate.

Then EP's tested - 25mm didn't work, got a fishbowl effect, but 17mm, 13mm, 10mm, and 8mm all fine.

10mm with 2x Barlow was pushing the ISO requirement too high - but maybe exposure compensation will deal with that.

All these got a focus using my standard EP holder.

Done and dusted in an hour flat!

Had a quick look at the EOS... wow! If Backyard EOS beats the standard one supplied with the camera it must be SERIOUSLY MAGIC.

Oh... and I haven't read the book yet! So, since, as per usual when new kit arrives I have 100% cloud cover tonight, I shall be curling up snug and warm with the book and finding out how many mistakes I made in my tests.

Verdict - much much easier than the Nikon was.

I don't know if it will work with AP, but when I was using the Barlows and so needing more ISO - the live view followed my changes so I appear to be seeing in live view what I'm likely to get as a saved image. The only thing I failed on (having saved the test shots in RAW + JPG) was getting the RAW shots to upload to the PC. They showed up in the camera's folder as local drive things (?). No doubt actually reading the book will solve this one. I am a very happy bunny!

[bus_ter]

There's no reason why you can't get great images with Nikon Dslrs. In fact they generally have lower noise sensors at high ISOs which is a plus. However life is a little easier with Canons. The way they process the images is better suited for astrophotography (google "nikon star eater") to see what I mean. Also Canon produce dslrs designed specifically for astrophotography with different filters that don't cut out wavelengths that are useful for astro images. Look at the 60Da for example.

[squeaky]

I'm sure the Nikon could eventually have produced results - but honest, I found it to be really hard work to get anything at all.

The Canon, at first touch in daylight tests was a lot easier.

OK, so maybe it's just me - but I'd rather risk some (slight?) loss of data or increase in noise when I can be sure of getting something "pretty reasonable", if not "good", in comparison to "theoretically excellent" which I simply don't have the skills or knowledge base to achieve.

Everything worked straight out of the box, so to speak, and the software with this model Canon beats what was supplied with my Nikon by a country mile.

Can't wait to start trying AP with this. If the weather doesn't clear up in a week I'm going to emigrate!

[Steve Ward]

Evening Sir ,

Glad to hear you're back on track .

I've just finished my months free trial of BYEOS , not that i got a month out of it......

Best thing about it for me was the intervalometer side of it ,

Didn't like the liveview , Canon EosUtil was much better for focusing i found .

EosUtil has a great testshot feature that doesn't leave you with spurious frames intermingled with the gooduns.

BYEOS also shoved an 'error' message up regularly and stopped working with no explanation losing me runs of frames on more than one occasion.

Am trying APT now , or will be , before i make a decision , may just get a cheap intervalometer .

I always prepare a folder on desktop before venturing outside and fill it with a load (15 or so) numbered sub-folders which makes life a lot easier to keep track of things in the heat of battle so's to speak. Much quicker to start a new subject in the dark and cold.

Hope you have fun with the new toy , i have no doubt that you will.

See you sometime soon.

Steve.

[squeaky]

Ah, I'd forgotten that I could trial BYEOS. I'll take a look at it after I've learned my way round Canon's EOS Utility. It's certainly impressive, though to be honest I have nothing to compare it against.

We're kinda drifting off topic now, since I no longer have a Nikon but do have the Canon - so I'll start a new subject - Canon 550D EOS first impressions.

[SamAndrew]

I feel like I should jump in here to defend the D3100 as I wouldn't want this thread to put an owner off of starting astro photography because they thought they had the wrong camera;

The main difference compared to a Canon for entry level photography is the auto dark frame subtraction, which will waste prime imaging time; you have to turn the camera off during the dark frame in order to cancel it and just save the RAW image

other than that, there isn't much in it between a Canon or a Nikon.

I'm not saying I would recomend a Nikon if you were buying a dedicated astro camera, as the Canon software will be an advantage once you get into imaging more seriously, and the good guides on modifying the Canon cameras are another big bonus. I would say your camera shop let you down here, but unless they are astrophotographers themselves then they are unlikely to realise.

Oh, and a tip for D3100 users - that Prime Focus plus Barlow limitation means that you MIGHT do better using the optical holder and an eyepiece instead. The recommended MINIMUM focal length is 15mm - so from my Celestron lens kit the 13mm "might" give a wider field of view - and you may just get away with using the 17mm. At least for setting up purposes. I never got as far as trying it.

The problems you have described in this thread really aren't down to the camera at all, but are due to the scope you are using, a focal length of 1.5m is very long indeed, and because the scope isn't designed for prime focus photography you are being forced to use a barlow, which has the effect of doubling your focal length to 3m! You will probably have to use a barlow with any DSLR, and this is the biggest issue.

Have a go at not fully extending the tube, and get rid of the barlow and this will make like much much easier.

This is the website that helped me out when I first started, http://www.astropix.com/HTML/I_ASTROP/TOC_AP.HTM

[squeaky]

Thanks for that Sam.

Yes, I think I pretty much came to those same conclusions - after having a good vent about all my difficulties and frustrations.

At the end of the day it was the lack of help available that really made the decision to change for me. Every time I (finally) solved a given problem and so could move up to the next step, so to speak, I would then encounter another problem... almost certainly much the same as those met by any novice... and again the lack of help, essentially what seems to be a very limited knowledge base compared to what you see everywhere for Canons, would make the task that much harder. I had no idea how many more steps I needed to take to get up to par with this AP lark, or how many more things I might have to solve; I was just tired of beating my brains out over the course of a week, or even two, per "how do I do this?". So I gave up.

It's not that I'm "thick". I'm "untaught". There's a difference

I can learn. Some from thinking things through and experimentation, some from reading and looking things up. But by 'eck it's not easy.

I don't know as yet how much difference there is in performance level between the Nikon D3100 and the Canon 550D because we've had lousy skies here and I had one brief chance for a trial and calibration shoot (too early in the summer evening for serious AP through a high haze and with a fair bit of LP) but my previous experiences with the Nikon were of some help, obviously, and I had time (yet again) to do plenty of reading beforehand - so I got that shot in an hour flat. As opposed to umpteen hours spread over six weeks weeks. I doubt that I'll ever really know enough to properly evaluate the difference between the two but at first glance the Canon does pretty much match the Nikon to my untutored eye. I can't take shots side by side now to compare and I binned all my original trial shots to clear some space on this laptop, so can't go back for review either. That'll teach me - I should have kept at least one set of original subs.

As you say - the long focal length of my scope doesn't help, so I'm looking into focal reducers. Not really sure how that works but it may be another way to help get Prime Focus. I'll be able to borrow one at some time in the next few weeks and will report back.

I also now have a Baader Clickstop Camera Adapter which looks as though it will allow me to remove pretty much all the various EP holders and nose pieces that currently have to sit in the optical train and so that might allow me to get Prime Focus without having to move my flex tube inwards. Again I'll report back.

It's another rainy day so I'm off to read up on those last two

[Dave]

You wouldn't get me to part with my D300 for anything. I still have my D70 too

Good Man!!!

[SamAndrew]

A good beginner book is Making Every Photon Count by Steve Richards

http://www.nightskyimages.co.uk/making_every_photon_count.htm

As you say - the long focal length of my scope doesn't help, so I'm looking into focal reducers. Not really sure how that works but it may be another way to help get Prime Focus. I'll be able to borrow one at some time in the next few weeks and will report back.

There are no cheap focal reducer options for newtonian scopes unfortunately, and a reducer will require even more inward focuser travel,

Shortening the legs on the tube is you best bet, I wouldn't spend any money trying to get a dobsonian to work with a DSLR

[squeaky]

There are no cheap focal reducer options for newtonian scopes unfortunately, and a reducer will require even more inward focuser travel,

Shortening the legs on the tube is you best bet, I wouldn't spend any money trying to get a dobsonian to work with a DSLR

Right, thanks