Adam J
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Posts posted by Adam J
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32 minutes ago, AstroGS said:
@Adam J @Stuart1971 I thought so too. We changed the orientation of the filter to eliminate this possibility and the results were more or less the same. Another thought was that Pertzval design OTAs might be more susceptible to such effects - especially on OIII @ 2.8nm. But, since the SII & Ha Antlia filters are excellent, I consider the OIII to be defective and will be returned.
I don't think it's the scope. The filter is suspect in my view and if a new filter doesn't solve it maybe the coating on the sensor cover glass is defective. Definitely contact your supplier.
It's actually potentially worse than what I have seen from the ASI1600mm pro on that target. On the 1600 it would be confined to only the two brightest stars and no others in that field of view.
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On 18/02/2024 at 13:03, AstroGS said:
@ollypenrice this is how it looks after (my personal best) stretching. I tried through the available Pixinsight tools (that I know of) to remove the halos but, since they are integrated in the nebulosity, I am finding it difficult to remove without leaving a residual shadow.
Interesting that you are getting microlensing from a ASI2600mm?? Anyone else ever had this? Are you sure your filter is the correct way around?
Adam
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I have started a general discussion of mobile power solutions in the thread below.
But I start by detailing my DIY power rig and as such I thought a link from DIY astronomy was also relevant.
Please reply in the linked thread not this one!
Cheers,
Adam
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Following a discussion Hijacking the HEM15 review thread I have started a dedicated thread here.
The system I have made and flown with on both Easyjet and Ryan Air is detailed below:
I take two of these LiFePo4 batteries:
They are 8Ah at a nominal 12 volts for 96Wh per battery
Batteries under 100Wh per pack are almost universally allowed on flights in carry on luggage.
You have to be really careful, not all will allow over 100Wh while FAA regs state up to 160Wh, some will allow this, but frequently this is limited to 2 packs and in some cases they do now allow a total (for all batteries) >300Wh. So you would not be allowed to take two 160Wh batteries.
This has been suggested:
Celestron Lithium 13.2 Ah LiFePO4 Powertank Pro | First Light Optics
But I like to keep it simple, everyone will let you take a 96Wh battery on a plane in hand luggage, you cant get tripped up by it.
But honestly that aside the Celestron power tanks is £235....
Here is what I put together for £120 pounds all inclusive using two batteries of 98Wh each for a total of 196Wh and that price includes a charger....so why anyone would pay for that power tank is beyond me unless you really did not pay attention in your GCSE physics and cant wire a battery to a connector and I really doubt that applies to very many people in this hobby.
This is 2x96Wh LiFePo4 batteries. The batteries each include a battery management system to prevent, overheating, over charging, over current, and over discharge internally as stock, I tested and it works.
I have attached cables two each terminating in a Female XT60 connector.
The batteries attach to a control box in parallel with three Male XT60 connectors. This means you get the full 192Wh without disconnecting a battery, you can also charge the batteries in parallel by connecting a charger to the third connector.
The Box contains a Battery charge monitor (top green) that displays percentage charge and battery voltage. Further more it contains a 12.2 volt regulator with boost (that way you can run the battery down to 11.2volts while still maintaining 12.2volts on the output (no low voltage issues), also it can make use of any battery or power supply from 8volts to 24volts and still output 12.2volts. You could even charge while in use. It also contains a 5volt regulator that outputs to a USB A-type socket so that any USB device can also be charged / powered from the batteries and finally a switch...
For me this is a vastly better solution than the celestron power tank and much much cheaper.
It then all attached to a power distribution box on the scope dovetail from one output and the second output powers the mount and mini PC.
Discuss:
Adam
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4 hours ago, Celerondon said:
I don't want to highjack this thread into a regulatory rabbit hole, but things will depend on which airline you fly with. The 160Wh limit is specified by CAA. But, depending on which airline you use you can either carry two 160Wh batteries, one 100Wh battery, or perhaps something in between. The relevant CAA regulations were linked earlier in this thread and the FAA regulations are easy to find but both authorities say that different airlines such as British Airways have final say so about batteries over the 100Wh capacity threshold. At first, I thought that British Airways might follow the lower limit but then I found this page. So, it seems as if most major carriers allow two 160Wh batteries and according to the British Airways guidance and other sources, you "do NOT need to contact the airline or inform staff at the airport that you are carrying this item."
Don
You have to be really careful, not all will allow over 100Wh and some will allow single 160Wh but not allow a total (for all batteries) over >300Wh so you would not take two 160Wh batteries. I keep it simple, everyone will let you take a 98Wh battery on a plane in hand luggage, you cant get tripped up by it.
But honestly that aside the Celestron power tanks is £235....what I suggested above is £100 for two batteries of 98Wh each for a total of 196Wh and that price includes a charger why anyone would pay for that power tank is beyond me unless you really did not pay attention in your GCSE physics and cant wire a battery to a connector and I really doubt that applies to very many people in this hobby.
As this has Hijacked the HEM15 thread for too long now I have made a new thread here:
That way we can get back to discussing the HEM15 which I want to hear more about
so please move battery discussion to the new thread.
Adam
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So looks like ZWO are bringing out a new cooled version of the ASI585mc and it's expected to be competitively priced as a camera to introduce more people into cooled deep sky imaging. Apparently it may land in the region of £600 pounds which really would be impressive if true.
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1 hour ago, adyj1 said:
£39! - that's an excellent price. I have similar 12v 8AH LiFePO4 batteries that I bought last August and paid £48. I was allowed to take two on a Virgin flight to the US - they had to carried in hand luggage, so just as well they are very light.
I also got a dedicated LiFePO4 charger from Amazon for £30.
I'll be using it to power my HEM27 in the field (bought after the US trip). [ weak attempt to get things back on topic 😉 ]
Ady
Yes I have taken them on a Ryan Air and a easyJet flight in hand luggage without issue. In the UK they did not even look at them. But in Spain they removed them and took a look at the capacity. All good.
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I just use this type of battery:
cheep and it works really well. Sized for airline travel with a battery management system included. All you need to do is make sure the terminals are covered for air travel and also buy a suitable charger. Why pay more.
Adam
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Also Wipe the ENTIRE filter wheel down it will be full of spores and you want them all dead.
Adam
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9 hours ago, pipnina said:
I noticed a strange vignette on my halpha filter during the last imaging session, and shon a torch down the tube to see if it were a spider or some such. Horrifyingly I saw spiderweb like fungus had grown to cover a sizable portion of the filter. I images RGB that night but the other day I opened the filter wheel to see Multiple filters affected, red in particular but none as severely as the halpha. On chroma's website they say acetone or pure alcohol is suitable but while my acetone did remove fungus from one filter, it left a misty haze behind and so I stopped in case the impurities caused further issues!
During this operation multiple filters seemed to have snapped or cracked retainer rings. I have to admit they looked cheap rubbish when I installed them from the zwo kit but I didn't expect to find £3000 worth of chroma filters held in by the screws alone...
I don't seem to have any spare clips so if they're available I will have to find replacements I suppose, as I will need to remove the filters properly to give them the thorough delicate clean they need to avoid damage but I can't reasonably put them back with broken retaining clips.
My next idea was to use distilled water from my film development station, which is very good stuff and leaves my negatives in pristine conditions of cleanliness as the final rinse. Pipetting it onto the filters to cause remaining dirt or residue to rinse off.
Maybe using the acetone or a more pure acetone or alcohol would be better?
At the same time I have to find a way to remove dried super glue from a panic repair to my EAF bracket that spilled onto the filter wheel. Acetone seems to dissolve it but so slowly I'd be there all year. I am terrified of damaging the paintwork and am trying to avoid scraping or sandpaper...
Oh dear oh dear. I've often cursed myself for buying chromas instead of far cheaper but nearly identical Baader or Astronomik but now with fungus issues I'd really really rather have cheaper filters that would be less stressful to clean!
Thanks in advance for advice!
James
Well for a start they are not nearly identical. I have recently seen results that show better contrast from chroma 8nm than Antlia 3nm filters.
But in any case you need to get it off as it fungus can be acidic and will etch the filter coatings if you don't get it off sharpish.
I would use what you have, acetone is recommended and you have some so use that, then wash it off with distilled water after that.
Don't worry about little water marks for now, just get the fungus off ASAP and worry about that later.
I personally use pure cotton buds to wipe the surface, the important thing it is to keep rotating the bud and use many many buds so your lifting the stain from the surface not just moving it about.
Adam
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3 hours ago, drivera said:
Hey,
I tried to quickly surmise my situation in the topic!
So in the UK it's been terrible weather for months and with limited time (can't image during the week) it was about 2 1/2 months since I have tried to image. I have a GT71 setup with a ZWO 533MC, on my GEM45 (don't get me started but won't be upgrading soon).
I went to image about 3 weeks ago on my first calendar cleared/clear skies and I suddenly couldn't get focus, even more, the stars were off and my mask couldn't pull any spikes. I always take my scope and gear all off, don't touch it, store it and return it for my next session. Something has gone wrong and maybe suddenly knocked (wife wants to blame a cleaner, and I want to blame the wife so we resulted in natural causes and force majure). I'm doing first tests on it on my next clear night such as removing the flatenner to see if it is that or not. Otherwise, something has damaged the scope and it seems FLO are manic busy can't do any tests, and I will see if Rother Valley can do a check. It's also out of warranty.
So...back to my main next question. I'm going to have to buy a new scope. I've loved the GT71 for widefield and it's beautiful but I would love to get into galaxies more. I have been trying but unsuccessfully identifying the right scope like a RC8/10 that would provide great images for galaxies, but under acceptable GEM45 weight (45lb/20kg).
I'll be imaging with my 533MC until in the next 4-6 months I'll step up to mono (not sure which camera).
What scope would you go for to image galaxies but can handle the weight on GEM45.Thanks!
Never heard of anything like that before.....very very odd. My bet is that it's something very simple that you have missed. The GT71 is actually a very simple but of kit you know. Perhaps some pictures and a sub will help people help you.
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2 hours ago, ollypenrice said:
I don't say that they are not intrinsically connected, I say that certain optics can perform relatively poorly on stars while performing well on extended objects. I think the relationship is not simple, that's all. Two instuments come straight to mind, the Meade 10 inch ACF and the RASA.
Resolution in imaging is also intimately connected with signal because, with more signal, you can sharpen more in software.
I would not expect to get O.85" out of the RASA's optics even though I do live on a mountain. I repeat that I don't need to, I need to get respectable resolution for a 400mm FL.
Unfortunately I cannot compare the resolution of my Tak data with my RASA because the sampling rates are so different, the Tak being under sampled. What I can say is that that I'm delighted by the extended object resolution I find in the RASA. This is a crop of the Pillars of Creation from a single frame RASA image which comfortably framed the Eagle and Swan nebulae together. Let's forget spot diagrams and look at pictures. Do you find anything to reproach in this level of visible detail from an instrument of 400mm focal length? I don't. What does the OP think?
Olly
Olly is that image Duel narrow band data?
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25 minutes ago, Icesheet said:
I agree the FRA300 looks great but then I’m surprised you think the FSQ has poor performance with the new flattener. Looks better corrected and smaller spots than FRA300 although can’t find any quoted RMS radius. The new reducer for the Tak does quote spot size though and it’s 1.6micron on axis, 1.9 at APSC and 3.9micron at full frame. Of course price difference aside.
it is possible they have improved it.
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12 minutes ago, Icesheet said:
Very nearly bought the FRA300 when I ended up with the FRA400. Probably should have tbh as it seems to have tighter stars than the 400. Still, I think I would prefer 400-500 now as I’ll use the Samyang 135 and have a Tak TSA120 at nearly 900mm FL. Seems like a nice set up, I’ve seen some of your images 👍
Now the FRA300 has a wonderful spot diagram, one of the few scopes that by claim at least would make use of 2.3um pixel cameras.
Adam
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18 minutes ago, ollypenrice said:
Although I know that Vlaiv does not agree with me, I do not believe that quality of stellar image necessarily equates to quality of extended object image.
Vlaiv is correct they are intrinsically connected.
OP is making an argument that 200mm aperture will resolve more than a 85mm refractor..am not so sure that true, I would say that for most of Europe unless you are at significant elevation both will resolve the same due to atmospherics but if you did take the RASA up the mountain your not going to get close to 0.58 from its optics.
Image quality is also about Signal to Noise as you cant get details with poor signal to noise to the RASA images will help in this case but the problem is that there is a point when more Signal to noise will no longer gain you detail.
So it depends on the target.
Adam
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5 minutes ago, Elp said:
What's the issue with RASA and mono? Changing filters?
The OP has an OSC camera.
Fitting the filter draw in for a start but yes no filter wheel. But I could also add off diffraction spikes form leads and not being even close to diffraction limited performance to that list.
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4 hours ago, Icesheet said:
I don't have enough clear nights to justify the amount of scopes I have so I’m going to thin down, again! I currently have a number in the 250-400mm FL range and I plan to sell them and replace with one dedicated imaging scope to mate with an ASI2600MC
Currently, the main contenders are:
Tak FSQ-85 (1.72”/px) 450mm FL, option of 330mm at f3.9
Pro’s
• Proven performer to APS-C (assuming good sample), even better correction with new flattener• Ease of use
• New reducer looks fantastic at f3.9 and relatively reasonably priced
Con’s
• Frustrating having to deal with back focus on what’s supposed to be flat field Petzval
• Risk of sample variation, expensive if collimation out
• Focuser not good enough?
RASA8 (1.94”/ px) 400mm FL
Pro’s
• Blazing speed
• Resolve more detail with >aperture?
• Cheaper
Con’s
• Collimation
• Not easy to get good correction at edge of APSC?
• Limited to ASPC and will need new filters.
According to MeteoBlue my local seeing is tends to be in the 1.5-2 arc sec range and I’m in Bortle 4 according to light pollution maps. Have no idea if this is the case but in either case the sampling of both scopes seems ok.
More important to me is to make use of the limited clear skies I have. I tend to not image one target over multiple nights so I want to collect as much as possible in one night! That of course favours the RASA but I need to balance that with ease of use. If there’s regular fiddling to be done I tend to give up and losing a night to issues is more of an issue than what’s gained from the extra photons on the sensor.
I’ve become quite picky with star shapes and sharpness. I’ve been using a FRA400 recently which is easy to use and gives me round stars but images appear a bit soft for me. I’m curious to hear what people might think would produce the sharper cleaner image out of the RASA/ Tak? Baby Q seems tighter with spot size etc but is this offset by the extra aperture of the RASA? I realise a lot of the processing tools we have these days can negate much of the negatives of both setups but I would like the easiest data to work with to start with.
Right now I’m leaning to the Tak but I would say that’s mainly because of my trepidation of dealing with collimation etc. Otherwise, I feel it’s a toss up.
Will cross post this on another site so apologies if you read this twice and thanks for reading and even better if you offer an opinion!
Chris
I can honestly and whole heartedly say i would personally not buy either scope. The flat field on the 85 is disappointing for a scope of its cost and the F2 RASA has always seemed like too much compromise in other areas (filters, difficulty using mono).
If spending that kind of money and wanted to be at 400mm focal length I would 100% without a doubt go with an Epsilon 130, no problems with filters and no problems with mono.
Adam
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20 minutes ago, Stuart1971 said:
No, but when you have spent an age of time trying to get that last bit of tilt out of your system, but still get a slight elongation in one corner, BXT can do wonders, and for some people who just can’t afford high end optics or mount, it’s a godsend to get half decent images….
So it has its place in my book…
Its actually hardly ever tilt causing bad corners from what i see, its just the go to explanation, its much more often a problem with collimation a problem would normally result in the OTA being returned or tweaked. I can just see it that in the future when you get a new refractor with collimation problems the manufacturer will just say why don't you just use BXT....
The above looks more like an optical issue than a tilt issue to me. I would be doing a star test not "fixing it" with BXT.
If an out of focus star test in centre field shows non concentric rings...I think it will, then it needs colimating as something has shifted in transport. Not sure if the cells on these are user colimatable. So maybe ask the supplier if this turns out to be the case.
As its showing on the short side of the sensor then its also possible to rotate the camera 90 degrees, if it stays the same its tilt, if gets mush worse its colimation.
It has its place as you say, but even a budget refractor should come well colmiated even if the polish / correction is not top notch and while fixing minor issues is great you should not convince yourself to accept less than what you paid for.
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8 minutes ago, Stuart1971 said:
That’s look pretty darn good, especially with a reducer, I bet it’s almost perfect with just the flattener…what did we all do before BXT, I think that has revolutionised processing for many people…👍🏻
We spent time making sure our optics worked correctly...some of us still do as BXT cant generate detail out of thin air.
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Many thanks, how about peak errors?
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On 09/02/2024 at 22:51, Ags said:
I promised to post my thoughts about the HEM15 when it finally got here, and it happily arrived tonight on a Friday evening, rather than the Monday next week the courier promised.
First off, FLO knows how to pack a box and everything was quite secure in masses of eco-friendly packaging stuffing. Careful excavation, ably assisted by astronomy dog Wurzel, revealed the HEM15 with its accomplices, an ASI120MM and AsiAir Mini. The plan is to primarily use the HEM15 with the AsiAir for visual, imaging and spectroscopy activities, with plate solving to make sure things get found. However, for planetary imaging and viewing, I think I might just set up with the HEM15's hand control.
I don't have a telescope that will really tax the mount - the heaviest thing I have is a C6 weighing in at 3.5 kgs. I may sell some things later in the year to buy a Classical Cassegrain 8" - at 8.5 kilos it would certainly be more of a test.
I am coming from an AZ-GTi and before that a 4SE mount. That makes this the first mount I have owned with a metal skin, and it seems in a different class . Everything feels very solid with no play and seems well-machined and precise. The DEC clutch is very small but cleanly loosens or completely tightens the DEC axis with a singe twist. There is no wiggle in the power input. The cables don't move when the mount moves. The handset is small but in my opinion the right size, not fiddly at all. By default it beeps loudly on each button press - an absurd default. Slewing without load at maximum speed shows smooth and almost inaudible motion, although Wurzle made it clear there is some noise in the hypersonic frequencies dogs can hear. Maybe someone younger than me would hear more of a whine.
I also tested the setup with power fed through from the AsiAir Mini. It is annoying that the Air must be daisy-chained to the mount via the handset, I presume the brains of the mount are all in the handset. It all seemed to work fine and the ASI120MM took a few pictures of my living room. However I didn't see how to control the mount via the Air - I had connected to it using the HEM27 option as the latest firmware still doesn't feature the HEM15 as an option.
it will be great to see some guide results. Be good to see a calibration plot too. Not sure you get that plot though on an ASI Air?
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1 hour ago, GasGiant said:
I work in an industry where we do lots of fabrication work among our 'normal' bread and butter work.
Hypothetically speaking. If someone were to manufacture tube assemblies to customer specs, is there any legs in that idea ?
We can also manufacture piers
C
Hypothetically how much would it cost me lol
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The rate of tech improvement in sensors is actually not as steep as some make out. After all you can only make things so good before [removed word] noise and LP are the limitations. As a result these older sensors are often underrated by the community. Someone who knows what they are doing with such a camera will put image someone with a new 2600mm used by an inexperienced imager.
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3 hours ago, scotttumsh said:
Can anyone help with a couple of issues i have with the star adventure GTi i have come accross.
No1 issue is tracking, star trailing even at 30 seconds, polar alignment is spot on so not that, both axis seem to be pretty stiff when balancing. The tracking says sidereal and on. The scope i have attached is the evolux 62ed so not overloaded either.the other issue is the redlight flashes at different rates and i cant find anything about that in manuals.
should say the mount is new as well only had it a week. Any advice/ help would be most grateful.Scott
Could be so many things and you have not provided much information, most likely is your not well polar aligned. Can we at least see a sub frame?
so please move battery discussion to the new thread. 
New camera, ASI585mc Pro
in Discussions - Cameras
Posted
Yeah but you can say that about anything second hand Vs new.
You can get a used 294mm for cheaper than a new 533mm....etc etc.