Can’t find a single star

[teoria_del_big_bang]

What flattener is it exactly, is it this one:

2019-all-new-adjustable-flat6aiii

[Alien 13]

11 minutes ago, HydrogenBadger said:

If it isn’t enough are there generic spacers I can buy? I guess it is worth getting a few spare to deal with when I try to fit the flattener. 

If you are using the focusser compression rings you can get either this or the more expensive WO one, you wont need two inch of extension with  a FF/FR.

Alan 

[inFINNity Deck]

Below diagram shows you how much space there should be between the flattener (assuming it is a Flattener 6 for GT71) and the chip. Your camera has 6.5mm from its front surface to the chip. So for the GT71 you need 65.82-6.5 = 59.32mm of spacers between the rear surface of the flattener and the front surface of the camera.

Nicolàs

 

Edited August 12, 2020 by inFINNity Deck

[teoria_del_big_bang]

Not if it is the new adjustable WO flattener in the link in my last post. The 11mm, 16.5 mm and 21 mm spacers that come with the camera are all that is needed. This will make the spacers 55mm in total. The adjustment on the flattener then has to be 9.1 mm which will equal 64.1 mm which is the recommended back focus for this flattener.

Steve

Edited August 13, 2020 by teoria_del_big_bang

[alacant]

2 hours ago, HydrogenBadger said:

Will I need to increase that to focus on stars

Decrease.

[HydrogenBadger]

12 hours ago, teoria_del_big_bang said:

What flattener is it exactly, is it this one:

2019-all-new-adjustable-flat6aiii

Yes it is this one. 

[HydrogenBadger]

11 hours ago, inFINNity Deck said:

Below diagram shows you how much space there should be between the flattener (assuming it is a Flattener 6 for GT71) and the chip. Your camera has 6.5mm from its front surface to the chip. So for the GT71 you need 65.82-6.5 = 59.32mm of spacers between the rear surface of the flattener and the front surface of the camera.

Nicolàs

 

Thanks very much for this. Very helpful. 

[inFINNity Deck]

Hi HydrogenBadger,

the diagram I gave was for this flattener, so please ignore it and use the following info:

Nicolàs

 

[teoria_del_big_bang]

1 hour ago, HydrogenBadger said:

Yes it is this one. 

Then with this flattener, which is adjustable, you should  not need anymore spacers than what came with the camera. 

Whilst the photograph I put on my previous post is not mine I think yours just needs to be exactly like that and the 11mm, 16.5 mm and 21 mm spacers that come with the camera are all that is needed.

 I have a WO scope, but not this one, and unfortunately was bought before the adjustable flattener came out so mine is fixed which means all the adjustment to make the back focus correct has to be done with spacers between the flattener and camera and I had to obtain 0.5 mm spacers to get it just right. With these adjustable ones that is not required as the fine adjustment can be done on the adjustment of the flattener. 

I am not sure where the image in the post from  @inFINNity Deck  came from, maybe that is the fixed flattener that was used before this new adjustable one, but it doesn't seem to tie in with any info I can find for this particular flattener.

EDIT - I am now had I have just seen the reply so that settles that (Thanks @inFINNity Deck 🙂 )

 

Looking at the Info on the WO website and the FLO website I would think it is as follows,

2019-all-new-adjustable-flat6aiii

william-optics-adjustable-flat6a-iii

The back focus for this flattener with the GT71 is 64.1mm is as below:

The distance from the front of the camera body to the image plane, without any attachments or spacers, is 6.5 mm.

The first thick spacer that screws directly to the camera is 11mm, you should also have a 16.5 mm and a 21 mm spacer with the camera. So 6.5 + 11 + 16.5 + 21 = 55 mm.

Back Focus needs to be 64.1 so 64.1-55 = 9.1 mm - So adjust the flattener by 9.1 mm.

The image below shows the distance from the end of the flattener to the image plane to be 55 mm (being made up by 1 or more spacers which you should have). 

Sorry if I have confused you, that was not my intention and hope you have the required information to set it up correctly when you fit the flattener.

Also whilst doing this I see why you need the 1.5 hex key, those grub screws are not present on my older WO scope it all just screws off. I guess yours is much more secure and cannot now come loose.

 

I hope I have helped anwyay rather than confuse you more 🙂 

Steve

Edited August 13, 2020 by teoria_del_big_bang

[HydrogenBadger]

2 hours ago, teoria_del_big_bang said:

Then with this flattener, which is adjustable, you should  not need anymore spacers than what came with the camera. 

Whilst the photograph I put on my previous post is not mine I think yours just needs to be exactly like that and the 11mm, 16.5 mm and 21 mm spacers that come with the camera are all that is needed.

 I have a WO scope, but not this one, and unfortunately was bought before the adjustable flattener came out so mine is fixed which means all the adjustment to make the back focus correct has to be done with spacers between the flattener and camera and I had to obtain 0.5 mm spacers to get it just right. With these adjustable ones that is not required as the fine adjustment can be done on the adjustment of the flattener. 

I am not sure where the image in the post from  @inFINNity Deck  came from, maybe that is the fixed flattener that was used before this new adjustable one, but it doesn't seem to tie in with any info I can find for this particular flattener.

EDIT - I am now had I have just seen the reply so that settles that (Thanks @inFINNity Deck 🙂 )

 

Looking at the Info on the WO website and the FLO website I would think it is as follows,

2019-all-new-adjustable-flat6aiii

william-optics-adjustable-flat6a-iii

The back focus for this flattener with the GT71 is 64.1mm is as below:

The distance from the front of the camera body to the image plane, without any attachments or spacers, is 6.5 mm.

The first thick spacer that screws directly to the camera is 11mm, you should also have a 16.5 mm and a 21 mm spacer with the camera. So 6.5 + 11 + 16.5 + 21 = 55 mm.

Back Focus needs to be 64.1 so 64.1-55 = 9.1 mm - So adjust the flattener by 9.1 mm.

The image below shows the distance from the end of the flattener to the image plane to be 55 mm (being made up by 1 or more spacers which you should have). 

Sorry if I have confused you, that was not my intention and hope you have the required information to set it up correctly when you fit the flattener.

Also whilst doing this I see why you need the 1.5 hex key, those grub screws are not present on my older WO scope it all just screws off. I guess yours is much more secure and cannot now come loose.

 

I hope I have helped anwyay rather than confuse you more 🙂 

Steve

Steve, thank you so much for this. Extremely helpful. I really appreciate the time and effort you have put into this response. 
 

Just need to get the hex screw driver to fit the flattener. 

Thanks again. 

[teoria_del_big_bang]

Your welcome,  I had all the same issues and needed help from others on this forum for all this when I started not that long ago so happy to help.

Believe me everybody in this hobby has had issues and evenings where nothing went right so don't get disheartened eventually it all make sense and things start to work 🙂 

Steve

[Grierson]

I can’t add to the excellent advice that you have been given above but it would be interesting to know what sort of relationship you have with your supplier. You clearly specified what you required and yet you had to add, to what must have already been a significant outlay, extra money for weights and with seemingly little advice. Given the small size of the market good dealers appear keen to ‘go the extra mile’ IMVHO.