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JGM1971

The "No EQ" DSO Challenge!

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Oh come in. Its like saying only formula 1 is a real race. With a bike you can also be a good racer. Its a hobby. I would say all the eq mounts are wrong equip. A space telescope is THE right equipment.

 

?:-)

Carsten

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I don't think that there is a right or wrong, it's equipment that allows one to achieve what one wants to achieve. If this thread achieves anything it is that it dispels the myth that to do any astrophotography one has to have expensive mounts accurately aligned, with guiding to boot (the so called right equipment).

Ian

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31 minutes ago, calli said:

Oh come in. Its like saying only formula 1 is a real race. With a bike you can also be a good racer. Its a hobby. I would say all the eq mounts are wrong equip. A space telescope is THE right equipment.

 

?:-)

Carsten

I would never say that. Formula one is a heap of moneymaking rubbish. I was a kart racer and racing cyclist. I thought the cycle racing was best of all.

23 minutes ago, SteveNickolls said:

I'm not going to throw my wrong equipment away, the images are as real as is the effort taken to get them.

Steve

 

Quite right, and I wouldn't suggest for a moment that you did.

17 minutes ago, The Admiral said:

I don't think that there is a right or wrong, it's equipment that allows one to achieve what one wants to achieve. If this thread achieves anything it is that it dispels the myth that to do any astrophotography one has to have expensive mounts accurately aligned, with guiding to boot (the so called right equipment).

Ian

I think there is a right and a wrong mount. A mount which tracks the sky without rotation is the right mount and one which doesn't is the wrong mount.

I repeat, I like this thread but I think it should be a thread about what can be done with an alt-az mount. It should not turn into a thread pretending that an alt-az mount is the right mount.

Olly

Edited by ollypenrice
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The thread will go where the individual contributors take it. There's no pretence. One thread extoling the trials, tribulations and successes of alt-az mounts is a breath of fresh air and inspiration to many.

Cheers,

Steve

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Like many, M42 is my first try at a DSO. Would love to know how to improve on it.

60 x 8 sec ISO1600 with Celestron Evolution 9.25 and Canon EOS60d

 

 

image.tiff

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47 minutes ago, ollypenrice said:

I think there is a right and a wrong mount. A mount which tracks the sky without rotation is the right mount and one which doesn't is the wrong mount.

I'm not sure whether your comment is a bit tongue in cheek Olly, but I can't let it pass without response :icon_biggrin:. One type of mount might be better than the other for astrophotography  (though that would depend on what you want from it), but you can hardly say that one is wrong and the other right. That's like saying for example that a reflecting telescope with an aperture of less than 8" is wrong, and greater is right, or that the f-ratio below f/7 is right, and above is wrong. And as you know, some of the largest professional telescopes use alt-az mounts (not simple ones, admittedly!).

47 minutes ago, ollypenrice said:

 It should not turn into a thread pretending that an alt-az mount is the right mount.

Or indeed, into a thread saying that an EQ mount is the 'right' mount.

Ian

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Well, we'll go round in circles if we're not careful. In astrohotography we use long exposures. Long exposures need to be made while tracking the sky across the whole image. Only an EQ mount can do this at amateur level. An Alt Az can only track in the centre. This is not a value judgement such as stating when reflectors become too small. It is a hard fact.

You're perfectly right about the professionals using alt-az but they use alt-az with derotators. (Way back in this thread I jokingly referred to one I've used.) The prfessionals don't autoguide, though. They use direct drive mounts reading absolute encoders. I know of no way of autoguiding a deroataed alt az, though Meade used to list a derotator at one time.

I'm a huge fan of alt az for visual and detest EQs for this purpose.

Anyway the people positng on this thread have done wonders and I don't want to come across as saying anything else!

Olly

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I predict a time in not far future where Encoder based altaz mounts are so cheap and equipped with single photon catching cams doing autostacking will just outperform any Amateur eq Mount. The signs are there. ?

 

Olly i don't mind your opinion but please(!) don't try to separate a community of hobbyist trying to have fun with such sayings. All photos from the stars are AP no matter how done.

Carsten

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9 minutes ago, calli said:

I predict a time in not far future where Encoder based altaz mounts are so cheap and equipped with single photon catching cams doing autostacking will just outperform any Amateur eq Mount. The signs are there. ?

 

Olly i don't mind your opinion but please(!) don't try to separate a community of hobbyist trying to have fun with such sayings. All photos from the stars are AP no matter how done.

Carsten

I wouldn't dream of doing so and don't believe anything I've said should be taken as divisive. If it seems that way then I apologise.

If the technology you predict comes to be then, wallet willing, I'll be in there!

Olly

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14 hours ago, ollypenrice said:

I like this thread, as I've already said, and I like your images. However, I'm not able to accept the phrase, 'The so-called wrong equipment.' It IS the wrong equipment. The right equipment for DS imaging is the equatorial mount. I think it's important to bear in mind that beginners will be drawn to this thread. For me this is an excellent thread about what can be done with what is, no bones about it, the wrong equipment.

Olly

IMHO what you are saying is like saying a "disposable camera is the wrong type of equipment for talking landscape photos" tbh.

When the fact it, it isn't.

To take the best (DSO) astro photos, yes you need EQ mount etc. But stating that astrophotography cannot be done without an EQ mount etc is, IMHO simply an incorrect blanket statement.

I agree with you that beginners could be drawn to a thread like this, and once again, in my opinion, its worth highlighting to those people that you do not "need" to spend a fortune to carry out some sort of astrophotography.  If this then helps more people get into the hobby that can only be a good thing, rather than seeing them put off by the cost of getting into some sort of imaging.

 

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19 hours ago, The Admiral said:

I am so at sea with PixInsight at the moment. But I managed to squeeze this one out of the pot!

After using Advanced Background Extraction to remove a strong green cast, I find that the targets are also left a bit green. Previously I tried Colour Calibration to remove the tint, but this time I used the Curves Transformation to lower the green channel before upping the saturation. I wonder if Colour Calibration removes the colour information too much. Not saying it is anything like it should be, but if anything, it shows I've a lot more to learn :help:

Ian

Colour calibration should always do a good job, and i don't think it removes any colour - in this image, use the structure detection turned on so that it picks up all the stars, and play around with the background levels so that the white reference mask it outputs contains only stars and the background reference mask contains only background. (ie no noise is included in either in error)

Then the Curves Transformation tool can do a lot to enhance colour - open it up, put the real time on, and then you'll see there are a number of tabs on it - 'R, G, B, RGB/K, etc etc'  select the last one called 'S' and that's saturation, drag up the middle of the curve a bit which will raise saturation in the weak saturated areas.  You might want to pull the top of the curve back down again if things start getting a bit too garish.  You can also go into the 'a' and 'b' tabs and put in a gentle s-shape curve in each to separate out the colours a bit more.  You would probably want to do this using a mask for the bright areas only, so you don't saturate background noise.

You can kill any excess green with SNCR

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apols, I posted the last comment without having seen this last page of the thread and ensuing argument - you'll have Olly saying DSLR's are the wrong camera too soon (kidding ! :evil6: )

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What this thread can do is help a person decide how far their astrophotography journey will need to be by helping them see whether what might be acheived without long exposures is going to keep them happy and provide a visual mount, or that the goal is more and therefore longer exposures and an eq solution is required. I love this thread it stops the hobby being so black or white.

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17 hours ago, Filroden said:

Like many, M42 is my first try at a DSO. Would love to know how to improve on it.

60 x 8 sec ISO1600 with Celestron Evolution 9.25 and Canon EOS60d

It would be nice to know what you have already done to process it. You probably need more total exposure time, that always helps. Even so, I've taken the liberty of just treating your image to a bit of contrast enhancement and sharpening in my photo processor and you may be surprised at what is already contained in the image. It's a question of teasing it out with the appropriate tools.

With an ALT-AZ mount, field rotation is something you need to minimize, but even so, exposures of 30s should be do-able as long as you don't get star streaking with your mount's movement.

56cdd5b895855_imageprocess.jpg.d166ea7f2

Ian

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1 hour ago, glowingturnip said:

Colour calibration should always do a good job, and i don't think it removes any colour - in this image, use the structure detection turned on so that it picks up all the stars, and play around with the background levels so that the white reference mask it outputs contains only stars and the background reference mask contains only background. (ie no noise is included in either in error)

Then the Curves Transformation tool can do a lot to enhance colour - open it up, put the real time on, and then you'll see there are a number of tabs on it - 'R, G, B, RGB/K, etc etc'  select the last one called 'S' and that's saturation, drag up the middle of the curve a bit which will raise saturation in the weak saturated areas.  You might want to pull the top of the curve back down again if things start getting a bit too garish.  You can also go into the 'a' and 'b' tabs and put in a gentle s-shape curve in each to separate out the colours a bit more.  You would probably want to do this using a mask for the bright areas only, so you don't saturate background noise.

You can kill any excess green with SNCR

Thanks Stuart, I'll need to look at this, re. structure detection and masking. Not at all familiar with those. I've already used the S tab to increase saturation, but found it just coloured the whole image a single colour, following use of the Colour Calibration tool. Early days!

Ian

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4 hours ago, Bobby1970 said:

 

To take the best (DSO) astro photos, yes you need EQ mount etc. But stating that astrophotography cannot be done without an EQ mount etc is, IMHO simply an incorrect blanket statement.

 

 

You are quite right and that is why I didn't say that. The thread demonstrates very well that it can be done with an Alt Az mount.

Olly

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4 hours ago, Bobby1970 said:

I agree with you that beginners could be drawn to a thread like this, and once again, in my opinion, its worth highlighting to those people that you do not "need" to spend a fortune to carry out some sort of astrophotography.  If this then helps more people get into the hobby that can only be a good thing, rather than seeing them put off by the cost of getting into some sort of imaging.

Hear, hear!

Ian

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Again, I agree. In truth Alt Az and equatorial mounts overlap in price so I don't think it's so much about the net cost as what you can do if what you have is an at az mount and don't want the bother or expense of changing. One of my biggest astronoomical regrets is firstly buying a wedge for, and then de-forking, my Meade SCT. As an Alt Az scope for visual observing it was fabulous, with a convenient EP position almost all over the sky and no flip. I heartily wish I had just left it alone.

Olly

Edited by ollypenrice
French keyboard - again!

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I don't think it is just cost, but also convenience. As one who has to drag all the gear down from upstairs and set up each time I do astronomy, particularly as I can't see the Pole Star from where I observe, an Alt-Az mount suits me just fine. Furthermore, I'm happy to take images which I know aren't top notch, but which at least allow me to visualize objects I'd have trouble seeing visually. That's not to say I'd be happy with any old result, it's still a question of getting the best from the equipment I've got. That's the challenge. One could do live stacking, but then that means even more paraphernalia that needs to be set up, a laptop, something to put it on, cables, a separate camera, whereas an imager in a box (i.e. a DSLR) is pretty minimalist. That's my take on it anyway.

Ian

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12 minutes ago, The Admiral said:

I don't think it is just cost, but also convenience. As one who has to drag all the gear down from upstairs and set up each time I do astronomy, particularly as I can't see the Pole Star from where I observe, an Alt-Az mount suits me just fine. Furthermore, I'm happy to take images which I know aren't top notch, but which at least allow me to visualize objects I'd have trouble seeing visually. That's not to say I'd be happy with any old result, it's still a question of getting the best from the equipment I've got. That's the challenge. One could do live stacking, but then that means even more paraphernalia that needs to be set up, a laptop, something to put it on, cables, a separate camera, whereas an imager in a box (i.e. a DSLR) is pretty minimalist. That's my take on it anyway.

Ian

Yes, the need for counterweights is the big GEM palaver. 

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1 hour ago, The Admiral said:

It would be nice to know what you have already done to process it. You probably need more total exposure time, that always helps. Even so, I've taken the liberty of just treating your image to a bit of contrast enhancement and sharpening in my photo processor and you may be surprised at what is already contained in the image. It's a question of teasing it out with the appropriate tools.

With an ALT-AZ mount, field rotation is something you need to minimize, but even so, exposures of 30s should be do-able as long as you don't get star streaking with your mount's movement.

56cdd5b895855_imageprocess.jpg.d166ea7f2

Ian

Thanks Ian

I've only used levels, curves, vibrancy and saturation on the image so far. I'm hoping to try some longer exposures this evening but I find even slight breezes ruin too many shots when I expose in the 15 to 20 second range and I don't think I've ever got a sharp 30 second shot where you can see rotation also starting to have an effect. 

Im also going to try and take my first flats. 

I have to say, I knew I could take some great shots of the moon and planets but I didn't expect I could dabble in DSOs. I can't wait for M13 to get high enough. 

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10 hours ago, ollypenrice said:

The prfessionals don't autoguide, though.

Ohh, we do you know! Except perhaps for sub-1min exposures, as the overheads in finding guide stars becomes too high.

NigelM

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3 hours ago, ollypenrice said:

You are quite right and that is why I didn't say that. The thread demonstrates very well that it can be done with an Alt Az mount.

Olly

My mistake. You did say that Alt/Az was the wrong mount for astrophotography, just to clear things up. ;-)

Which, the existance of this thread proves to be an incorrect statement.  :-P

Edited by Bobby1970

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20 minutes ago, Bobby1970 said:

My mistake. You did say that Alt/Az was the wrong mount for astrophotography, just to clear things up. ;-)

Which, the existance of this thread proves to be an incorrect statement.  :-P

We'll have to disagree amicably on that. You think the alt az mount is the right mount for AP and I don't. This doesn't mean we have to duel to the death with loaded pistols. (I hope. I don't have one!)

Olly

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