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Old 25-02-2021, 10:51 PM
evltoy (Wayne)
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First Attempt at Guiding

Hey All,

My new NEQ6 mount come in 2 days ago and I was eager to get out and use it. My first night/time I was able to polar align and everything worked like a dream. love this mount and can see how owners like it.

On the 2nd night I decided to give guiding a shot for the first time. Hooked up my ASI462 and NEQ6 to PHD2 (took 30mins to setup with ASCOM drivers). I left everything as default in PHD2 and away I went. I was very surprised at how easy the whole process was to get started considering I have never owned a SW EQ mount and guided before.

I took a photo at the end of my 4hr session (finished at 4am) of how my mount/guiding has been performing.

Can someone translate to me on how it performed and where I could improved? Due tot he moon being out last night I was only able to get 90sec exposures

Cheers
Wayne
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Last edited by evltoy; 25-02-2021 at 10:53 PM. Reason: :)
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Old 25-02-2021, 11:38 PM
Rerouter (Ryan)
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It looks almost like you have rotation in your 90 second sub, the stars trail about some point in the image, instead of in a consistant direction,

which to me would seem like your polar alignment was a little off, PHD has "drift alignment" which could help with that.

Your DEC backlash seemed to get much worse towards the end, was that something like a merdian flip or something else changing up the balance? that could also be a contributing factor, but frankly it doesn't explain the stars trailing in different directions in different parts of the image.
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Old 26-02-2021, 12:02 AM
evltoy (Wayne)
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Thanks for the advice Ryan. I did here about drift alignment in PHD2. I will read up more on this and give it a shot... baby steps

There was no meridian flip done. I was on soft ground so not sure if this caused the issue over time. also as this mount is very new to me I'm still needing to zero in on the Polar Alignment
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Old 26-02-2021, 12:05 AM
Startrek (Martin)
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Guiding numbers look OK, under an arc sec in both Dec and Ra
Your guide Star has an unusually high SNR at 107 ( itís a wonder itís not saturated, most guide stars are usually around 20 to 50 SNR
Did you use the auto select guide Star in tools or did you manually select a guide Star , itís best to let PHD2 to find your guide Star
Next time your out try the guiding assistant , it will measure how your mount is performing and give you an approximate polar alignment error. Your polar alignment could be way out ??
How did you polar align and what was your error ?
Did you calibrate near the celestial equator and within 20 degrees of the north meridian, this is the preferred location as advised by PHD2 as it allows for a good calibration when Dec is near 0
Early days yet but you have a few things to check in your PHD2 guiding before you can look at your scope and image train and get to the bottom why your stars are eggy or flared with fairly good guiding numbers
Hope some others can chime in too and provide help
Good luck !!
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Old 26-02-2021, 07:43 AM
Alchemy (Clive)
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From what Iíve seen you have kept the adjustments under 2 arc secs which should allow for much longer exposures.

Points to consider. But not necessarily each a cause of issues here

Check your subs prior to stacking every now and then something can cause a bump or two ( clouds etc youíd be surprised at how thin cloud is difficult to see, I have a thermal camera which picks out stuff I canít see )

Coma etc, correct spacing for your field flattener can cause flared stars particularly towards the corners, (Iíd look at this one first) , just reconfirm you have correct spacing for yours, donít be scared to experiment a little to see if you do get an improvement, itís possible your flattener is generic amd who knows if it is exactly the same with every scope, once you have it set itís done.

Movement in the image can be caused by sagging in the focuser, I know Iíve done a focus prior to imaging and given I donít have an autofocus setup, Iíve forgotten to lock down the focuser, you can see how much movement there is by gently wiggling the camera, prior to doing your run.

As for polar alignment find a system which works for you, everyone has their favourite, I like the Polemaster but each to their own. Iím spoilt as I have a permanent observatory so I can rock out each night ready to go, I would have thought, if you can set out 3 concrete pavers in the back yard to put the scope on, any soft ground issues will be gone, given itís such a tiny amount of movement for alignment. Then once you have alignment mark the pavers so itís repeatable each night, the less time you spend setting up the better.

As you said baby steps, and it looks like youíre off to a good start.
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  #6  
Old 26-02-2021, 10:07 AM
Startrek (Martin)
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Wayne,
Attached is some PHD2 guiding information I put together a while back which may be of some assistance
Cheers
Martin
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Click for full-size image (IMG_8328.jpg)
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Attached Files
File Type: pdf PHD2 Guiding Procudures and Tips.pdf (37.1 KB, 18 views)
File Type: pdf PHD2 Guiding Information.pdf (23.8 KB, 15 views)
File Type: pdf PHD2 Multi Star Guiding.pdf (22.4 KB, 14 views)
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  #7  
Old 26-02-2021, 05:20 PM
AdamJL
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I don't know what's wrong with the guiding, but that's a fine image
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  #8  
Old 27-02-2021, 10:31 PM
evltoy (Wayne)
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Hey All,

Some valuable feedbackÖ Thank you so much for your time.

Its good to know my guiding numbers are ok consideringÖ this is what I wanted to know before I started playing around.

I did use the auto select guide star to try and understand what PHD2 would like as a guide star. Also note my guider scope and guide camera were not 100% focused (was too excited). Not sure if that caused what you have highlighted with the SNR numbers.

In regard to polar aligning my mount, I just did a 3 star align, then ran the Alignment through the hand controller on Siris (it was close to Zenith). No polar scope ☹ Next time after my Polar Alignment I will do a 3 star and Polar Alignment again to zero in more and choose a star instead of HC default.

With my stacking in DSS Ė I was lazy and just pick the last 50 odd of 170 as the moon was up high and images were over exposed and yeah, there were light clouds around.

Some else commented on another image of mine and said check your backspacing. I was using my 8Ē SCT with the celestron reducer/flattener -> Celestron T adaptor -> T-Ring-> DSLR. The first night I added an extra 5mm spacer between the T Adaptor and T-Ring and I found the stars to be the sameÖ You be the judge. Going by the spec on my camera Iím within 1-2mm of the required backspacing for the reducer.

Quote:
Originally Posted by Startrek View Post
Wayne,
Attached is some PHD2 guiding information I put together a while back which may be of some assistance
Cheers
Martin
Martin Ė Thank you very much for the Docs, I'll spend a little time reading up as Iím now on holidays on the south coast with both my scopes (I have a good wife )

Quote:
Originally Posted by AdamJL View Post
I don't know what's wrong with the guiding, but that's a fine image
Thank you very much. I too though it was ok for first attempt on new equipment and guiding
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  #9  
Old 27-02-2021, 11:28 PM
Startrek (Martin)
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Wayne
Glad to help
I noticed you are using a Skywatcher EQ6 mount ??
You mention about a 3 star alignment in your reply
Just remember that a star alignment and polar alignment are 2 different functions of your telescope mount
Polar alignment is to align the central axis of your scope to the south celestial pole or very close to , using the Azimuth and Altitude bolts of the mount
Star alignment is to provide your mount with a starting point in the home position ( or SCP position ) and input date , time, latitude data etc.. and move or slew it to 1,2 or 3 Stars positions on the same side of the meridian , sync it to each star position to achieve an accurate pointing model through sophisticated algorithms built into the memory of the mount. Once Star alignment is achieved it is saved. If your polar alignment is very poor with large error from the start , your Star alignment will also be inaccurate with stars outside the field of view and drift etc.., Iíve only ever used a 2 star alignment which is good enough for accuracy ( a 3 star alignment seems a bit unnecessary)
If you are using the EQ6 mount you donít need a view of the south celestial pole to polar align with those damn neck breaking, eye squinting polar scopes ( Iíve never used the polar scope to polar align as both my imaging locations have no clear view of the SCP , so Iíve been using the Skywatcher Syncan Polar Alignment routine for 4 years now with great success
There are many capture software programmes which include a polar alignment feature but the Synscan is fine as you already have the handcontroller
Most times I can be be polar aligned to 1 arc minute or below in 10 to 15 minutes which is more than satisfactory for PHD2 guiding
Attached is my procedure for the Synscan polar alignment routine if your interested in using it ( I use my old DSLR in the main scope ( newt) and my laptop with BYEOS alignment feature ) Years ago before the laptop I used a wide view illuminated reticle eye piece to centre stars.
Hope I havenít advised above things you already know , apologies if I did
Cheers
Martin
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  #10  
Old 28-02-2021, 03:08 PM
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muletopia (Chris)
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Locating tripod

Wayne,
When I used a tripod I did not use pavers. I set the tripod up level and correctly oriented. I then used 3 300 mm long half inch steel water
pipe pieces as follows.


Sink the pipe that will receive the south leg until it just protrudes from the ground and put the conical tip of you tripod south leg in it, Sink the pipe to receive the east leg and leave plenty protruding. Use a spirit level to check N/S level and sink the NE pipe until it holds the tripod N/S level.


Repeat the operation for the north west leg until the E/W is level.
Place your tripod tips in the pipes and if any residual leveling is required ad just the legs.Then LOCK the legs to the final lengths.


This makes for very accurate tripod placement, if you can leave the mount in place with a towel over it and a plastic bag over the lot
setting up is very easy, (mark the Dec balance point).


BTW As many others do I use Sharpcap's Polar align routine, quick ,easy and accurate.


Chris
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Old 08-03-2021, 02:29 PM
evltoy (Wayne)
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the eggy stars continue!

Hey Guys,

Once again thanks for all your experiences & knowledge in helping me out.

I'm currently still on the south coast and it has been kind to me with no rain since I have been up here. With this, I have been able to leave my neq6 + 8" SCT/ED80 out (covered) for most of my stay. I have also managed to use the Park feature which works 100%... what a time saver!

OK. so based on everyone's feedback here and what I have read here is what I have done.
1- Mark up mount; Home location, RA, Dec clutch etc.
2- Rough polar align Tripod (south)
3- Level tripod with a builders spirit level on solid ground
4- Place head on tripod and balance in both Dec & RA with OTA + gear
5- Set up clocks in both Dec & RA
6- Give a little eastward heavy by adjusting weights (lower)
7- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel)..
8- Polar Align on Sirius (through DSLR finder, centered) very close
9- Turn off mount

10- Reset clocks & turn on mount
11- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel).. very little adjustments
12- Polar Align on Sirius (through DSLR finder, centered) Bang on centered!
13- Turn off mount

14- Reset clocks & turn on mount
15- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel).. spot on, no adjustments
16- Polar Align on Sirius (through DSLR finder, centered) no adjustments required
17- Using the Park feature from here on after end of session

My Polar Alignment Error readings are ďMel=+000,00í00" Maz=+000,00í05Ē

My guiding through PHD2 is default settings with letting PHD2 selecting a guide star (SNR was 4 or 5ish) and total error was around .30-.40 (running for 3-4mins) before shooting.

Some said to check my back focus spacing as the eggy stars were in different directions on the outer sides of my frame. From no spacing (using the Celestron reducer + T-Adaptor and T-ring) to putting a 5mm spacer I saw no difference. And here is an image I did last night with a 10mm spacer.

I selected the best 33 images in DSS and the exposure time was only 90sec per sub

Can anyone provide some direction on why my stars are the way they are on the edges?

Cheers
Wayne
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  #12  
Old 08-03-2021, 08:16 PM
Startrek (Martin)
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Quote:
Originally Posted by evltoy View Post
Hey Guys,

Once again thanks for all your experiences & knowledge in helping me out.

I'm currently still on the south coast and it has been kind to me with no rain since I have been up here. With this, I have been able to leave my neq6 + 8" SCT/ED80 out (covered) for most of my stay. I have also managed to use the Park feature which works 100%... what a time saver!

OK. so based on everyone's feedback here and what I have read here is what I have done.
1- Mark up mount; Home location, RA, Dec clutch etc.
2- Rough polar align Tripod (south)
3- Level tripod with a builders spirit level on solid ground
4- Place head on tripod and balance in both Dec & RA with OTA + gear
5- Set up clocks in both Dec & RA
6- Give a little eastward heavy by adjusting weights (lower)
7- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel)..
8- Polar Align on Sirius (through DSLR finder, centered) very close
9- Turn off mount

10- Reset clocks & turn on mount
11- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel).. very little adjustments
12- Polar Align on Sirius (through DSLR finder, centered) Bang on centered!
13- Turn off mount

14- Reset clocks & turn on mount
15- Do a 3 start Alignment - Default HC brightest stars (Sirius, Alpha Centauri, Rigel).. spot on, no adjustments
16- Polar Align on Sirius (through DSLR finder, centered) no adjustments required
17- Using the Park feature from here on after end of session

My Polar Alignment Error readings are ďMel=+000,00í00" Maz=+000,00í05Ē

My guiding through PHD2 is default settings with letting PHD2 selecting a guide star (SNR was 4 or 5ish) and total error was around .30-.40 (running for 3-4mins) before shooting.

Some said to check my back focus spacing as the eggy stars were in different directions on the outer sides of my frame. From no spacing (using the Celestron reducer + T-Adaptor and T-ring) to putting a 5mm spacer I saw no difference. And here is an image I did last night with a 10mm spacer.

I selected the best 33 images in DSS and the exposure time was only 90sec per sub

Can anyone provide some direction on why my stars are the way they are on the edges?

Cheers
Wayne
Wayne ,
Just went through your procedures
I assume your using an EQ6 mount with your Synscan handcontroller
Firstly are you using the Synscan handcontroller to Star align and Polar align ?
Iíve only ever needed a 2 star alignment ( one of those stars being your polar alignment Star )
Secondly why are you repeating all your processes twice as you only need to polar align once ( if your happy with the error )
Thirdly Iíve never seen anyone polar align to the low numbers you have displayed which are are unbelievable
Lastly you donít need to adjust the setting circles ( clocks ) on your mount ( I just use them to set home position on the mount and thatís it )
Yes with Synscan you can save your alignment data and when you power up again you select option 1 ďstart from park positionĒ
I just have a query with your Synscan polar alignment procedure ( did you use the PDF file I sent you to carry out the Synscan polar alignment routine ?)
Cheers
Martin
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Old 08-03-2021, 08:51 PM
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The_bluester (Paul)
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The "Fishbowl" effect is commonly spacing. Which scope was that Orion shot with? The ED80 I assume given the field of view? Do you have a flattener/reducer on it?

Assuming the ED80 and a flattener or reducer/flattener, it looks like the camera might be spaced too far from it.
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Old 08-03-2021, 09:04 PM
evltoy (Wayne)
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Quote:
Originally Posted by Startrek View Post
Wayne ,
Just went through your procedures
I assume your using an EQ6 mount with your Synscan handcontroller
Yes I have a NEQ6 Pro v5 H/C with the latest firmware

Quote:
Originally Posted by Startrek View Post
Firstly are you using the Synscan handcontroller to Star align and Polar align ?
Yes I am. And selecting the stars advised by synscan

Quote:
Originally Posted by Startrek View Post
Iíve only ever needed a 2 star alignment ( one of those stars being your polar alignment Star )
From what I have read 2 or 3 star alignment is ok. I do 3 just because I want to... personal preference

Quote:
Originally Posted by Startrek View Post
Secondly why are you repeating all your processes twice as you only need to polar align once ( if your happy with the error )
In the manual it says doing this 2-3 times to get low Polar align numbers. My first round was in the high mins, then once I did it again I was able to get those numbers down.

Quote:
Originally Posted by Startrek View Post
Thirdly Iíve never seen anyone polar align to the low numbers you have displayed which are are unbelievable
I'm very anal with my measurements (builders side of me). All I can say is try doing 2 or 3 polar alignments to narrow in on the numbers Every target I hit I was bang on in the middle of my DSLR view finder. I did however spend 2.5hrs dialing it all in.

Quote:
Originally Posted by Startrek View Post
Lastly you donít need to adjust the setting circles ( clocks ) on your mount ( I just use them to set home position on the mount and thatís it )
Yes. this is why I was doing this, to set home positions. The DEC (I think) was moving after every alignment. I was preparing for the Park feature and may need to release the clutch once powered down. I understand it didnt play a role in my alignment.

Quote:
Originally Posted by Startrek View Post
I just have a query with your Synscan polar alignment procedure ( did you use the PDF file I sent you to carry out the Synscan polar alignment routine ?)
Cheers
Martin
I did read all your documents (thank you) and got some solid information from it (balancing and setting east heavy for backlash was from you .. and also trolling youtube and reading the synscan manual.

The process/workflow of alignment was very much the same as using my celestron evo mount with a wedge so this wasnt too new to me

Cheers
Wayne
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Old 08-03-2021, 09:11 PM
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I'm not 100% sold on your focus, but I'd suggest finding a nice bit of the sky with no nebulas or anything of interest and take an exposure with nothing but the stars.


I'm seeing that the trailing isn't all in one direction which makes me think that it's not guiding/alignment , rather backspacing. An image with nothing but stars will help figure it out. Given you're in Melbourne we should have a clear night by 2030 ........


Edit, I've added a picture to give you an idea of how incorrect back focus can affect the image.
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Old 08-03-2021, 09:14 PM
evltoy (Wayne)
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Quote:
Originally Posted by The_bluester View Post
The "Fishbowl" effect is commonly spacing. Which scope was that Orion shot with? The ED80 I assume given the field of view? Do you have a flattener/reducer on it?

Assuming the ED80 and a flattener or reducer/flattener, it looks like the camera might be spaced too far from it.
Errr! I was told to add more spacing!!! I went from no spacers, to 5mm then on this Orion image I went to 10mm

All images I have posted are with my Celeston C8 (non HD) with reducer, T-Adaptor (all celestron) on my Nikon D80

my first image without any spacers can be found in the below thread. The difference here is no guiding and using my evo mount on a wedge.
https://www.iceinspace.com.au/forum/...d.php?t=189005
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Old 08-03-2021, 09:22 PM
evltoy (Wayne)
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Quote:
Originally Posted by xa-coupe View Post
I'm not 100% sold on your focus, but I'd suggest finding a nice bit of the sky with no nebulas or anything of interest and take an exposure with nothing but the stars.


I'm seeing that the trailing isn't all in one direction which makes me think that it's not guiding/alignment , rather backspacing. An image with nothing but stars will help figure it out. Given you're in Melbourne we should have a clear night by 2030 ........
I always keep my focus shots before I image for troubleshooting. This was taken within 20mins of shooting Orion
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Old 08-03-2021, 10:01 PM
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xa-coupe (Jeff)
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Looking at the chart I have ... I'd *guess* it's too close but it doesn't really fit that model given... except that the centre is pretty well spot on. I also note the guiding graph is very choppy even though it is well within what is a good alignment ... there may be a clue in that but stuffed if I know. You have PHD2 version 2.6.9 which should have the multi star guiding ability, if you turn that on it may well make your guiding even better.



Save yourself a lot of grief and invest in SharpCap pro or one of the polar alignment cameras and align that way. I struggled for a while with aligning on an NEQ6 (still haven't worked out why I can't get it to work through the handset, but I've moved on!) and was convinced to stump for SharCap Pro ... and all my alignment worries just disappeared. One a good night (in Melbourne that's very rare!) I can get 10 minute exposures with no trailing.... and if I can do that, anyone can !



On the upside, you are producing great images pretty well off the bat, we are already at the final tuning stage. Took me ages to get to that point.
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Old 09-03-2021, 12:52 AM
evltoy (Wayne)
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Hey Jeff,

Thanks for the back focus attachment. That really helped me out.

I went through some of my images (both with and without the reducer) and what I found was; without the reducer my stars are round at the edges while with the reducer it looks like my back focus is too far out.

The part that gets me is I'm running the celestron reducer F6.3 with the celestron T-Adaptor designed for the celestron SCT C8. What is more interesting is that my issue has been around for many moons and Celestron hasnt done anything about it ie. bring out a shorter T-Adaptor.

https://www.cloudynights.com/topic/5...cer-corrector/
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Old 09-03-2021, 12:29 PM
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The_bluester (Paul)
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Aha, wrong assumption on my part on what scope you were using.

As far as I know, if you are using the F6.3 reducer/corrector on an SCT, the warp speed versus fishbowl effect is reversed compared to a traditional refractor and reducer/flattener combination, so fishbowl equals too close, warp speed too far. I have to play a little with my C925 soon so I will be able to confirm that. It is very slightly a fishbowl effect and I was going to add 5mm to see if I can flip it to warp speed to confirm. Once I am sure of my spacing I was going to get a custom spacer done up.
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