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Showing results for tags 'focus'.
Found 36 results
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Hi everyone! As I said few days ago in my presentation I recently got my first scope (skywatcher 127) and over the last days I tried to test It. Due to impossibility (temporary) to bring the scope in a decent location to make observations, I had to test it from home through a window (and under the sky of London - not the best at all). So i know that quality is of course affected. On the other hand, I am sure that the performances are worse than I could expect also under these conditions (maybe you will correct me) and would asks for opinions to improve. As a (mainly) planetary scope, I did not have a lot of choice: no Moon, Jupiter and Saturn out of my field of view. I pointed at Mars. First sight, I see the very big central obstruction. I played with the knob of the focus to get rid of the big black spot in the centre of my target and here you are the issues that I would like to talk about: 1) the target became very small (ok) but still was not focus (very blurry and not a lot of clues to get atleast the shape of the planet well defined - can imagine to find any detail on it ) 2) Also the colours did not convince me as no other colour than a light yellow was visible 3) Changing the eyepiece (10 instead of 25) for a magnification of 150x did not improve the situation: probably the image was even worse, more blurry with more irregular shape than before, no ability to focus at all. Differences from before : bigger (but still much smaller than expected) and very little variation in colours (I believe I saw a bit of orange). To complete, later, I tried the scope to stars: Orion costellation was visible from my place and tried to all the stars. Although still a bit blurry (the brightest stars), I had impression of more sharp view, differentiation in colour and better shape (stars almost like a dot). Moreover, to give you a final idea, Mars (at the best focus I could get) did not appear that much bigger than Betelguese. What do you think I can do to get better results? Could be a scope problem or some adjustments needed? Unfortunately I have no comparisons. Thank you, Hope I was not too long -
I’ve just acquired the above (birthday prezzie!). It’s a nice finder, and a definite boost from the 7x30 bundled with the scope! However, I’m struggling to get anywhere near focus with my Pentax K50 on the end of it... anyone know why? There’s no focus mechanism to speak of, other than the objective lens’ mounting thread... -
I spent the full night out last night and got 6 hours of Ha lights on the Bubble and the Horsehead. Reasonably pleased with the results, but even though I followed my usual process and got good focus statistics in APT, I am slightly out of focus with roundy stars and some are even slightly donutty. Samples are attached below. Problem: - After getting close to spot-on focus, the APT Bahtinov Aid showed a focus distance oscillating from -0.02 to +0.02. Seeing seemed good to the inexpert eye. Not so sure about transparency as there was some thin, wispy cloud throughout the night. So, I started the night's imaging with focus 'Close' rather than 'On' focus. - Different subs show different quality stars, ranging from small donuts to circles. Background information: - HEQ5 Pro Rowan; SW Esprit 80 with field flattener, SW stock manual Crayford focuser; ZWO EFW Mini; Baader 1.25" 3.5nm Ha filter; ZWO ASI1600MM Pro binned 1x1 @ -20c. - AA Starwave 50mm guidescope with ZWO ASI290mm Mini guidecam binned 2x2. - All subs are 300s, gain 139, offset 10. - Polar alignment with Sharpcap to 17 arcsec ("Excellent"); capture with APT; guiding with Phd2. Focus with Bahtinov mask and APT Bahtinov Aid. Stacked in DSS with Darks, Flats and Dark Flats. - Mount is well balanced in RA, but is very camera-heavy in Dec. - PHD2 guiding was around 2"/px. Imaging pixel scale is 1.9"/px. Questions: - Do I put the round stars down to seeing, given that the Bahtinov Aid focus distance was bouncing equally above and below zero? - Can poor seeing cause the donut stars? - Would an electronic auto-focuser do any better in this situation? - Would the Seeing Monitor in Sharpcap give useful information? I didn't think to use it last night. - Could my guiding performance, and possibly the Dec balance, have affected the image quality in this way? - What are my options in future - abandon imaging for the night? Bin all images in software 2x2 or 4x4 to sharpen the stars at the expense of lower resolution? - Other suggestions? Sample 1: Detail from a single 5-min sub of Bubble nebula at 100% showing round stars, and a blurred bubble. Sample 2: Detail from a different sub of the Bubble nebula at 400% showing donuts Sample 3: Detail from a 5-min sub of the Horsehead nebula at 100%, showing both round and donut stars Finally, both images stacked, calibrated and stretched, scaled to 4x4 in Gimp. 28x300s Ha on bubble, 22*300s Ha on horsehead.
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Hi all, I've been dabbling for about a year and am having a lot of fun. Nothing too serious and I don't have mega expectations but I'm starting to wonder if my images could be sharper and there's something I'm missing. I'm attaching a picture which is the best 10% of a 3 minute video with 500d 'bolted' straight to the 200p f5 scope. No filters...no barlows...just camera straight on. It's sharpened and saturated after the fact so in every way this is the sharpest I can get it. I've always had the same issue whether it's with a single shot, stacks of shots, or stacked video. Views through the eyepieces (circle-T 12.5/25) are mega sharp! I'm happy that collimation is very good and it was a remarkably clear night tonight. All in all I'd be pretty happy with this image (maybe over exposed a bit...) if the craters with shadows didn't make me want to rub my eyes. Thanks in advance for any thoughts or advice! -
Hey there! So if you have a telescope as mentioned in the title, you probably noticed that the focus wheel stops working after a bit. Well If you look under the focuser you can see a small metal piece with 4 screws on it. You need a Philips head screwdriver to unscrew these, WARNING there's a lot of superglue(which actually isn't needed at all) so wear gloves!after you've unscrewed the metal piece a small black 2 ended piece should fall out. If it didn't fall, take it out. Now place your focusing wheels back without that small piece that fell out and screw everything back in. The remaining black piece that fell out should probably be thrown away. Now just don't focus out to the max and everything should work just fine! I hope this helped(btw I'm new here so i might've butchered the terminology) *just let me know -
Hi, I bought some Williams Optics Binoviewers. They appear very nice quality but I cannot achieve foucus with them on a 5" Celestron Newtonian, FL = 650MM fr = f5. I have not used binoviwers before today and I bought them primarily for my new telescope which hasn't arrived yet, a Celestron 9.25 CST. I wanted to try the binoviwers out on the 5" today but could not achieve focus. I also tried using the 1.5 x Barlow that came with them. Is there a reason they won't focus? Do you think they will be OK on my bigger scope? Thanks. -
Can I reach focus with a DSLR and a focal reducer like with a barlow because my telescope does not have enough inward focus . -
Hi i own Celestron 130EQ which comes with 20mm erect EP and 10mm EP.... i bought a GSO ED 3x Barlow... The focus is not very sharp while using Barlow... Is it the EP at fault ???? Is it worth upgrading to Kelner or a Plossl ????
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Hello all, I’m a newbie...that will become very apparent in the next few sentences! I have a Celestron Nexstar 130 SLT and have a desire to take up astrophotography, I started with a few reasonable shots of the moon with my iPhone and have bought a Skyris 236C with no success. I would be greatful for any tips or advise on how to focus the moon for a start, I have uploaded a couple of photos one with the iPhone and one with the Skyris taken at the same time. TIA, Tony.
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Hi, i just wanna share a in depth review that i made on how the Primalucelab Sesto Senso works, and how i actually runs an autofocus routine with it. you can watch the whole review on my youtube channel here:
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I came across a video on youtube of a flymesh bahtinov , not focal length dependant has anyone ever tried this method before ? mesh he used is approx 1.5 mm sq and one half of the mesh is at 45deg to the other half ,found after i purchased a mask for my mak but still need one for my 130pds . https://youtu.be/IeUs7pFwMJw
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I've had my telescope (the Galileo G-872 refractor) for several years now and have been able to view planets in quite a bit of detail such as the rings on Saturn and the red spot on Jupiter. But recently every time I have tried to focus in on any planets (I've tried Mars, Jupiter, and Saturn) all I get are big grey dots. I am still able to focus on the moon with great detail but the planets still remain to be big grey dots. I have tried several times over the past few weeks in all different conditions and locations, I've cleaned the lenses, I've tried all of my different lenses and attachments and nothing works! I would really appreciate some help from someone who is maybe a bit more experienced in these matters than I. -
I'm brand new to this site, but I'm having an issue with my Celestron Powerseeker 127eq telescope. It's brand new right out of the box today. I have another telescope, Zhummel Z10, but the celestron just won't focus. It gets so close to focusing and just needs a little more. Any my help is appreciated thank! -
Hello, Am very new to this so apologies right from the start. I have recently just bought a skywatcher akyliner dobsonian 200p and i set it up. However the image is very blurry even when i remove all magnification and just look into the primary mirror eveything looks very blurry including the moon or nearby trees etc. I am unsure what the issue could be as i am eager to get started on my stargazing! Could someone please assist me or at the very least point me in the right direction. Kind regards -
Hi All, I'm very very new to this - so be gentle with me! I've inherited a Helios 150 telescope which I'm learning how to work. I observed the Moon through this a few years back, and it was brilliant, and I'm keen to share the sight with my children. The problem is I can't seem to focus the view finder. I can find the Moon of the spotter scope, very clearly, but when I look through the main eyepiece - a PLOSSL 10mm - I can see the light of the Moon in the back ground , but can only seem to focus on tree branches that are in the foreground- very clear relief - in the foreground. What am I doing wrong, and how do I fix it if possible? Very grateful for any replies. Thanks. -
Hi All, New challenge I am running into. When I add a filter wheel on my Bresser AR102s I run out of travel when trying to focus in. I have removed all the extensions and still can't focus in. Am I out of luck or is there something I can do? I am reading up on Focal Extenders am I heading down the right path? Thanks for your help. -
I have yet to be entirely happy with the focus on my pictures. When cropping them quite heavily (I use a DSLR, so smaller DSOs need a bit of cropping) the stars always feel a bit bloaty and look out of focus - much more than the image from the full frame. I have been using the focus aid in APT, checking out the FWHM tool. I don't know much about the science behind it, but my understanding is that the number needs to be as low as possible. Last night I was focussing and tweaked it down to around 1 to 1.5 - obviously it was fluctuating with the atmosphere/interference, but I thought that it was a pretty good score. I locked the focus very carefully, making sure that I didn't change the figure - I usually tighten half-way, check the value and then re-do it (if needed) before locking it down completely. I only twigged tonight that DSS shows a FWHM maximum on the light frames after it has checked them and, when I looked for the images I took last night, the FWHM figures were coming out at over 4.5. I am presuming that this is far from ideal focus, but is also a long way from what I thought it was. Is there any relation between the FWHM measurements in APT and DSS? Is there a reason for the discrepancy or am I just going to need to be even more careful with focussing? Are there vital settings in APT that I need to set? Will check for more scope related settings next time I get out. Might also need to get the Bhatinov mask out rather than relying on just APT Focus Aid. Thanks, as ever, for any thoughts
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Hi, Decided to have a go at a Bahtinov Mask today. I used the generator at http://astrojargon.net/maskgenerator.aspx to create an image which I printed on a laser printer. This was then taped to a piece of thick black card and the slots carefully cut out using a scalpel. I left some tabs of card around the edge. I then took a strip of black card and joined the ends so it fitted around the end of the scope. The front was then attached via the tabs and it was all taped up with black insulation tape. No stars out tonight to test it on so had to make do with a distant street light. Not ideal but it shows the principal. Very happy with this simple tool and can't wait to try it out for real. The mask front cut-out with tabs around the edge Assembled In focus Out of focus
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So my birthday just past so money to splash on astro stuff , i will have my 1000D modded by juan at cheapastrophotography and also have ordered an autofocuser from deepsky dad https://deepskydad.com/autofocuser i know they can be done DIY but this is a neat package and costs about the same as a SW autofocuser and a hitechastro focusmaster and i`m no electronic wizard and pavel seems to have a good product and works with ascom and confirmed it works with APT i will update in a few weeks time when hopefully i will have received and tried out .
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Hi all. after receiving my scope yesterday I went outside for about half an hour with it and was quite impressed on how easy everything is to set up and use. However I have two questions that I would like answered. When viewing at the moon using my 25mm eyepiece I could see a blue and orange haze around the left and right side of the moon. Was this because I didn’t have eyepeice focused probably or is there another reason? And also while focusing I had a lot of vibration is there a way to reduce it. Today I tried to get my red dot focused aligned with my telescope and I think I’ve managed o do it correctly but was concerned that my target was to close. My target was the Ariel on the roof top as I didn’t have any clear targets that were far away I had to choose that. I managed to get it aligned probably but heard that the targets were supposed to me further away? Man Thanks
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Hi SGL Wizards, I'm using an ED-80 with HitecAstro DC Focus, and am controlling it via SGP Pro. I've got autofocus working well (hooray!) but notice that each night the Focus Control's Current Position number gets larger and larger. For example, a month or so ago it was around 9000 for focussed stars with a H-a filter. Tonight it's 12884. Is this normal? I'd expect the number to be absolute, i.e. always around the same number but with some slight variations given temperature and the like. Thanks in advance, - Lee -
Hey guys I'm new to telescopes and well I have tried reading up on possible fixes, nothing works. First day I used it I was able to get a clear image on the lowest power inserting a 20mm eye piece and it would focus. Attempted my first night to look at Mars. Well it was a big blur and nothing worked. Next day I was attempting to look at a mountain and no matter what I did or try it remained blurry. Focus dial is free moving but the image stay as a massive blur. With no eyepiece it's still all a blur. If I look through it backwards there is a clear image however looking from the eyepiece it remains blurry. Im not sure what to do now. Any ideas? -
Good night, I have a Shoestring Astronomy automatic focuser. But it does not memorize the absolute position... Will it be necessary to add encoders in order to use it on a full robotic setup? I'll use SGP. Thanks so much, Aleix
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I am using a Baader Hyperion 36 mm 72° eyepiece with the Starwave 152mm Refractor and cannot get focus unless I use extensions for visual - for imaging it is imposible. Any Ideas ? Ernest Ernest
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Before anyone says it, I have got and fitted the short shoulder-less nose piece and removed the 5mm extension ring it comes with. With that out of the way, the DMK41 arrived today. I ordered the short nosepiece with it, and putting them on the PST the camera body is flush with the end of the eyepiece holder on the PST. It isn't getting any closer. In a quick and frustrating play, I just can't find focus. The sun spent most of the time hiding behind clouds so I didn't get much time, but I went near enough end to end on the focus scale. Before I gave up the sun was behind a TV aerial and trees, and using that as reference I know I can focus closer by rotating the knob clockwise. Infinity should obviously be the other direction, so I wound it as far as I dare anti-clockwise. It hits some resistance and by this point the knob sticks out quite far. So I'm hesitant to go further. Is this normal? Should I keep turning or will something fall apart before I hit an end stop? Any other tips? I did manually adjust the exposure so the sun wasn't blown out, but I haven't really had time to play with the settings yet. Given the sun has gone down now, I'll obviously can't try again until tomorrow (weather allowing).
