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The Moon with 8''


astrolulu

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@astrolulu I have been looking at collimation in more detail over the past week or so and I have to say that it has made a noticeable difference to my 200P. I know you have seen those latest images since I collimated it, so I won't post them here. I have just got a copy of Star Testing Astronomical Telescopes by Suiter and it certainly makes the concept of collimation a lot clearer and more scientific.

Your latest image is, as always, stunning. It is the standard I am  now aiming for and collimation is certainly helping.

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Hi Mandy, Your photos are getting better and better! It's worth remembering that the "quality of a razor blade" is primarily due to sticking to simple, though often burdensome rules. One of them is taking care of collimation of course. But the second primary is the height of the object above the horizon. I've learned that I don't even try to start working if the object is too low on the horizon. The impact of this factor is often underestimated, but it is absolutely crucial. This is why I had a longer photo-break. It was just that the Moon only glided over the horizon, and I was limited to viewing it with small refractors.

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13 hours ago, astrolulu said:

Hi Mandy, Your photos are getting better and better! It's worth remembering that the "quality of a razor blade" is primarily due to sticking to simple, though often burdensome rules. One of them is taking care of collimation of course. But the second primary is the height of the object above the horizon. I've learned that I don't even try to start working if the object is too low on the horizon. The impact of this factor is often underestimated, but it is absolutely crucial. This is why I had a longer photo-break. It was just that the Moon only glided over the horizon, and I was limited to viewing it with small refractors.

The Moon has been horribly low, especially when near full. Now that it is climbing again, I'm going to up my game. I've just started planning my deepsky rig, but intend to keep going at the Moon as it is my favorite target. I now have a 300PDS and will eventually drop the ASI178MM in it and point it at the Moon. I'm learning a lot about collimation and, like you, finding out how much improvement it makes for so little effort.

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300PDS + ASI 178 is a great set that should provide you with truly spectacular results! But - high above the horizon. The larger the diameter, the more crucial it is in my opinion...

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1 hour ago, astrolulu said:

300PDS + ASI 178 is a great set that should provide you with truly spectacular results! But - high above the horizon. The larger the diameter, the more crucial it is in my opinion...

100% right, high altitude for this baby! Before we get to high quality imaging of the Moon with this, I need to stiffen the tube as it flexes far too much, so I reckon on adding another set of tube rings and fitting two long Losmandy dovetails 180° apart with shorter ones 90° round from them. Then, I just need to build a mount to carry it, as it will be well over 30 kg with everything on it. First impressions are that the mirror looks good and it is now close to collimation. The last part of the equation is getting my skills up to scratch!

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Nice result, again! Here is my effort from 04:30 this morning. I went outside at about 04:00 to check on the sky and Moon and, although the Moon was looking a little hazy, the stars were rock steady with not even a hint of twinkle, so bad back or not I had to grab the 200P and set up. The Moon was still quite low in the sky and I was shooting over rooftops, but nothing could be done about that. I pointed the scope and camera at the Moon and it was blurred and hazy. A quick twist of the focuser and it literally snapped into focus just like with an excellent refractor - such is the power of good collimation! I zoomed in on live view and there was no wobble or shimmer, whatsoever! I have never seen things so still, so I ran a few frames off and could see that the scope was still cooling. I then grabbed a load of images at native focal length before deciding I had to try the telecentric focal extender under these conditions. I still need a spacer for that! I grabbed a couple of hundred frames and shot a couple of videos of the Moon drifting through the frame. Looking at the videos when I got in, it was obvious how perfect the conditions had been, with no shimmering or wobble that I could discern. The attached photo is at 2.4 m FL with the D800 doing the imaging, best 25% stacked in AS3., then processed in GIMP. My result does not match yours, but I am slowly improving.

Moon_20230909_Stack_Compressed.JPG

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Hi Mandy, you're making great progress, but you can't beat the laws of physics. Your camera has too large (4.8?) pixel for such optics - such a pixel size would require a focal length of over 4 m to match the image resolution. At the moment, you lose a huge part of crucial small details that determine the final effect. Diameter of 200 mm and a focal length of over 2 m is a good set for a 2.4 nm pixel - such as, for example, the ASI 178 camera, which I highly recommend. It's great that you are investing in optics, but the camera is the "second leg" - and here the expense would not be very large, while the progress in photo quality could prove groundbreaking. Please check this: http://www.wilmslowastro.com/software/formulae.htm#CCD_Sampling

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@astrolulu Thank you. Yes, indeed, there is a mismatch for maximal results and I really need to get set up with the 178MM. I'm in the process of obtaining the bits I need in order to do this. Perhaps, I should have used the D3200 with it's slightly smaller pixels (compared to D800), but I had no idea the seeing was going to turn out as good as it did. If tonight is similar, I'll go with the D3200 - closer but not there. I guess I could have stacked my 2x Barlow with the focal extender and gone for 4.8 metres. I was just too concerned with grabbing images whilst the conditions persisted.

That link looks very useful. Thanks again. I'm learning lots, here.

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Sorry, I understood earlier that you are just planning to buy the ASI 178. If you already have this camera at your disposal, forget about the DSLR!

A focal length of 4 m with a 20 cm mirror is, in my opinion, definitely too much and there is no point in trying to do it this way. Previously, I've mentioned matching the pixel size to the resolution, but there is also - simply - the question of native, optical resolution of the instrument. A 4-meter focal length will not show you more details at this diameter, it will only reduce the field of view, make precise tracking difficult, and Barlow will soften the image unnecessarily. My advice: hide the Barlow and DSLR cameras deeeeeeeeeep in the drawer, you now have everything you need to get an optimal image!

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@astrolulu I've had the ASi 178MM since the last Mercury transit, but not used it since. I do not currently have a laptop that is working, so I am going to have to buy some longer cables to view it's output from my living room. I have a tablet that, apparently, I can use for focusing, then I'll switch to the PC and do the image acquisition from my living room using ASI Studio or similar. So, until the cables arrive, I'm stuck with the DSLRs.

Everything you say makes sense, but is not technically feasible just yet.

My list of equipment appears in my signature.

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@astrolulu I have an i7 quad core laptop, but Windows has given up the ghost. Maybe the best way forward would be to put Windows 11 on it, or even Linux if we are only using it for image acquisition. I can always process on another PC.

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Your colour processing skillz are awe inspiring as always.    Your results are the main reason I have not sold off my colour cams - I suck working with colour,  but for even the faint possibility of doing similar work one day,  I keep them.

 

Clear skies

 

Mike

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Thanks, definitely don't give up on color! To be honest, lately I have had a tendency to limit my interference with color. Similarly to sharpening - I still think that I am acting too aggressively and one step back would improve the overall impression of the photo. For example here - I tried to sharpen very gently and minimize color manipulation. Someone may say that it is almost monochrome - but maybe the Moon is just like that?

When it comes to color, it is worth remembering the IR-cut filter. ASI 178 has it in a protective widow, ASI 183, which I am currently using, does not. And it gave a visible color difference. I took these photos using a Baader IR/UV-cut filter and the color returned to normal...

COPERNICUS-2023-09-07-15x67x77x90.jpg

 

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10 minutes ago, astrolulu said:

Thanks, definitely don't give up on color! To be honest, lately I have had a tendency to limit my interference with color. Similarly to sharpening - I still think that I am acting too aggressively and one step back would improve the overall impression of the photo. For example here - I tried to sharpen very gently and minimize color manipulation. Someone may say that it is almost monochrome - but maybe the Moon is just like that?

When it comes to color, it is worth remembering the IR-cut filter. ASI 178 has it in a protective widow, ASI 183, which I am currently using, does not. And it gave a visible color difference. I took these photos using a Baader IR/UV-cut filter and the color returned to normal...

 

Yeah...  I have to put a UV/IR cut in my 678MC,  bot not on my  QHY 5III 485C.   I LOVE my 183MM and am still looking for a 183MC non cooled used.   They are out there.   I have grid problems with the 678,   and my colour sucks the worst with my QHY.    Other than the grid artifacts,  I got a couple of acceptable colour results,  but nothing great.

Thanks for encouragement....  I will learn one day.

I am in agreement to your thinking on sharpening..... though I prefer the slightly punchier colour you usually have - still VERY restrained in comparison to many and I think you usually hit it spot on.   You are correct I believe though,  I think the above lovely shot is likely more "real",   but I am in favour of a LITTLE exaggeration myeslf.  :)))))

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9 hours ago, Mandy D said:

@astrolulu I have an i7 quad core laptop, but Windows has given up the ghost. Maybe the best way forward would be to put Windows 11 on it, or even Linux if we are only using it for image acquisition. I can always process on another PC.

Honestly, I use Windows myself and I don't know which acquisition programs have versions for other operating systems. It seems to me that the Sharpcap I use does not have a different version, unfortunately. However, FireCapture, which has quite similar functionality, has versions for Mac, Linux and Raspberry Pi.

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  • 1 month later...

After a long vacation from Photoshop, I'm back to processing materials from September. 10th of the month, 5:30 a.m. Only 20% of the disk is illuminated, which allows us to see objects on the western edge in different lighting than usual when we observe the Moon during more civilized hours.

SCHILLER-2023-09-10-15x50x90x90-ASI-183.

 

 

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8 hours ago, astrolulu said:

After a long vacation from Photoshop, I'm back to processing materials from September. 10th of the month, 5:30 a.m. Only 20% of the disk is illuminated, which allows us to see objects on the western edge in different lighting than usual when we observe the Moon during more civilized hours.

SCHILLER-2023-09-10-15x50x90x90-ASI-183.

 

 

Very nice! This is one of my favorite regions of the Moon.

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Thanks Mandy, I went to bed after 6 a.m., but I'm glad I made it this far because the opportunity to photograph this area in such light doesn't come around often. This time the Moon was quite high despite the phase.

And the second hemisphere, with a view of, among others, on Reiner Gamma. As we know, it is an albedo object with no special relief, so it seems that it will be less visible in such flat light. However, photos taken in the previous days show that it is quite the opposite and that only in such lighting conditions did this formation become visible in a clear and contrasting way.

 

REINER-GAMMA-2023-09-10-15x50x90x90-ASI-

 

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Your Lunar images are incredible! The way I can zoom in as far as my phone allows, the clarity and fine detail just staying rock steady is inspiring!

The single images I took this morning are fair, but then I zoom in and they wash out!

Like you said earlier, I put it on using my Canon camera.

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Thanks! Unfortunately, it happens with DSLR cameras that their pixel size is too large in relation to the diameter and focal length, which results in the loss of fine details. I use cameras with a 2.4 nm pixel and it fits quite well into various configurations that I use around 8" - e.g. SCT with a 2-meter focal length, or Newtonian with a 2x Barlow lens. You can check the sensor requirements here: http://www.wilmslowastro.com/software/formulae.htm#CCD_Sampling

The second thing is the scaling of the image - I always reduce it in relation to the original and only by sharpening the appropriately reduced version can I get the impression of full sharpness of details.

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One step back - to September 9. In the foreground the Sea of Moisture, with the Gassendi crater. The two large craters on the terminator's edge on the left are Longomontanus and Wilhelm, and the bright central object near the edge of the shield is Byrgius. This usually inconspicuous crater, in this light, begins to show ambitions to take over the function of capo to tutti capi. Ambitious considering it is only 19 kilometers in diameter...

MARE-HUMORUM-2023-09-09-15x58x90-ASI-183

 

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