Solar eclipse experience and advice

Hi All,

In light of today's fun with Venus I got myself some shade 14 welders glass, which only arrives the day before so I could not test it out, or cut the glass to size.

I tried to slot it into one side of my Cokin P filter holder, but found I could not got a crisp focus of the sun. Perhaps it was because of the angle of the glass, but I was wondering other people's experience if they could offer some advice if they have used the same type of glass, which is about 3mm thick.

I used it to look at one of our halogen down lights at home and can see the globe properly, but the lens won't get a crisp focus (glass not cut to size as yet). Maybe it is the 70-300mm lens, but again, advice would be nice.

Anyway all this driveling on is because there is a total solar eclipse in Nov and I am hoping to enjoy it to its fullest in Cairns, and I am wondering if anyone else is planning on going? I am thinking of hiring a F2.8 70-200 + 1.4 TC for the event as no one stocks a long enough lens at a large enough aperture, and I think that F3.5 @ that distance will be better than the 200-400 4.5-5.6 as the same focal length.

Anyway, I hope that initiates enough discussion and I hope to see some of you at least in November.

Pax

 

Get a proper solar filter. Don't be bodging it up. If you are going to DIY then at the very least get proper solar filtering film.

Sign up here if you want proper advice from people who do this stuff for a living/frequent hobby:

http://www.iceinspace.com.au/forum/index.php

 

Hi Menthu_Rae,

Using Shade 14 category welding glass is a recommended solution. I am not really interested in using a screw on filter, and many films are not suitable for using with the slide in Cokin filters, as you look at taping in the film, then trying to remove it can move the lens and you have to re-adjust the setup.

All a bit messy for what I am trying to achieve.

I'll jump on IIS forums though and see what people are doing there.

Geoff

 

Get the Baader solar film (make sure its the proper type for photography) and make a screw on filter. A drop-in filter system is sure to have light leakage around the edges which at the least will effect the shot and at worst kill the camera. (There are a few photos floating around of cameras with melted plastic that has jammed the mirror or destroyed the sensor from people who thought ND filters or welders glass was safe enough.) If you're really intent on being picky about making a cokin then buy a clear cokin filter (sky/uv/very-faint ND) and wrap Baader film around it and tape at the edge. Maybe sandwich the film between two clear glass filters. Solar photography is not just about blocking light and there are reasons solar telescopes have a special construction different to regular telescopes.

 

I certainly do like the idea of wrapping the film around an existing filter I have, as it gives the flexibility without resorting to a screw on.

It seems people certainly have strong feelings about not using shade 14 grade welders glass even though it seems to be a suggested option on many sites I looked at.

The last thing I want to do is to kill my camera sensor or shutter, especially as I might have a D700 inherited by then, and plan on hiring for the lens. I don't want to break any of that.

Another option which was mentioned was to use a mail poster tube which will drop over the lens and allows easy removal. What do people think about that.

Am I to assume also that because there has been no mention that there aren't others planning to be in Cairns for this event?

Pax

 

The Baader film is pretty cheap (for what it is, around $30 for A4 sheet) and is specifically designed to allow you to take photos of the sun and filter out all the nasty (non-visible) parts of the spectrum. The stuff coming from the sun can generate a lot of heat inside a lens assembly and inside the camera body and Baader film will help protect everything properly for prolonged use when you're camera is pointing at the sun. Plus its optical clarity is damn awesome, some of the devices I put pieces onto were wrinkled a fair bit but there was zero distortion when viewing...the clarity is honestly better than a lot of lower-end glass filters I've seen.

Welding glass is designed for a different purpose. While mostly the two products have a significant overlap in what they can do its what is/might be missing from the welding glass that would have me concerned. You've seen what a magnifying glass does to things when you focus the sun onto them and a camera lens is doing the same thing focusing the sun onto a delicate sensor, not to mention the mirror that directs the focused view through the eyepiece on a dslr. Sure it'll let you take one photo of the sun, so do ND and polariser filters too. I wouldn't want to risk damage to my eyes or camera by trying to dodgy something. Especially to save a few bucks or because its a "neater" solution.

The welding glass also won't be anywhere near as optically clear so the clarity of the shots will be reduced. I've used all sorts of things in the past to try to photograph the sun and nothing came compare to the Baader film (I haven't tried any of the better solar filter options yet). Getting a clear shot without hazing was almost impossible and even the very biggest of sunspots appeared to be faint in the shot (could have been camera noise and wishful thinking it was a sunspot .

The Baader will give you a very clear white light image of the sun and nice clear sunspots. Wrapping one to a cokin uv filter or similar will work nicely, add an orange filter to get some contrast and a visually appealing sun. Whatever solution you end up using just try to make sure that internally the only place light is entering the lens is through the filter. Light leaking in around the edge of the filter or filter assembly will bounce around inside (especially off the Baader which is mirrored on both sides) degrading the image you can get.

Mail poster tubes, Pringles cans, bits of plumbing pipes are all good for making a slip-on lens filter. Just make sure its clean inside, give the inside a spray of matt black before you start and maybe get some thin black foam to line the inside to make sure you don't scratch your lens but mainly to make sure you get a good light seal. For one of my scopes I used some plumbing piece (looked like the plumbing equivalent of a step up ring). To attach the Baader film I would cut a piece 1cm or so larger then the end of the pipe and lay it on a clean flat surface then run some tarzan's grip around the end of the pipe and sit it glue down onto the film to set. Then a bit of electrical tape to flatten the excess film to the outer edge and tidy it all up. Easy and neat and no light leakage. So yeah, tubes of all types are fine, just make sure they are made of something that blocks light well, paint the inside matt black and add anything you like to block light from sneaking in the rear and mucking up the shots. For my telephoto lens I found a metal lens step up ring that was sort of like a conical shape and an inch deep that I covered the end with Baader film. Looks very neat and works well, had to find a tupperware container to turn into a filter case for it but its all good.

One last thing is all other methods for getting shots of the sun I've used involve slower shutter speeds. I've no idea about welding glass but Baader you can shoot hand held (for the transit I was using a 500mm lens with 2x teleconverter shooting 1/800 iso100 f16 and very happy with the results.

Good luck, but I still wouldn't recommend the welding glass because of the possible risks to your eyesight as well as the reduced image quality.

 

Mate,

It certainly sounds like you've done a ton of this and I REALLY appreciate the advice.

I've got a warming Cokin filter too. Given the Baader film (sourced a small bit) gives the sun a white hue, I think the warming filter will work well.

Have to try it out when I get back from Ko Samui.

Pax

 

I live in Cairns, and will be keen to catch up with other togs during the event. I am yet to fully scope out the locations, but I am looking at close to the city rather than brave the road north first thing in the morning.

 

Yep I'll be heading up there in November, a total solar eclipse is something a lot of people never experience. I'd say the most essential thing is to not get to caught up in the photography, you've got 2mins to experience it with your own eyes. Intervalometer is going to be my key piece of equipment I think.

I found this page really helpful http://joe-cali.com/eclipses/PLANNING/2012_beginners/index.html

 

Some notes for those planning on coming up for the eclipse:

If you have not booked accommodation already, you're probably going to be sleeping in backpacker accommodation.

The best place to see the eclipse will be just south of Port Douglas, where there will be just over 2 minutes (2:05) of totality at 0640 am. (note: no parking, narrow road with limited places to pull over and everyone else wanting to get up there will mean you either claim your spot days in advance, or don't bother)

However, Cairns itself will have 2:00 minutes of totality - I am yet to properly research things, but with any luck the sun will have cleared the mountains to the East before the interesting stuff happens.

Alternatively, slightly inland around the Mt Molloy or Julatten will also give you the same deal, with fewer people and better chance of good clear skies.


A good map:

http://xjubier.free.fr/en/site_pages/solar_eclipses/TSE_2012_GoogleMapFull.html

 

Just checked, there's still some expensive stuff left, but I can't afford expensive... Maybe it's an epic road trip and sleep in the car kind of thing.

 

Our spare beds and floors were booked out months ago.

 

Solar Eclipses are a truly amazing experience.

I was lucky enough to go to the 2002 Total Eclipse in Ceduna (In South Australia), this only had 34s of totality so it was hardly enough to even take it all in, let alone try take a photo.

Even to this day I still remember the *gasp* as the sun completely dissapeared behind the moon. People were dead silent for 10seconds or so before they started clapping and cheering.

If you have the chance in any form to get there, do it, it's well worth the experience. We slept on the floor in a local school as all other accommodation was booked out months/years in advance.

I wish I could make the trip up, 2 minutes of totality would be *amazing*.

 

Hi Dark O,

These are some good tips actually. I had already had a look at prices for hotels and knew I was spending in excess of $200 for a night.

What are the local constabulary like up there, as I would imagine many people sleeping in cars on the side of roads would be happening trying to get a good spot too.

I think that side of the road near a farm would be good if staying away from the coast, but don't want to incur anyone's wrath, or a fine, if staying in a car.

If you are going to scope out areas, I just had a look at google maps, and I wonder what areas like Holloways beach/Environmental would be like.

I might even contact Half Moon Bay golf course and see if they mind some encroachment, or Yorkeys Knob boat club. the sea walls might be a good spot for viewing.

Ohhh the fun I am going to have finding somewhere.

If anyone is interested in sharing for the night, then we might be able to get a 3-4 bedroom place easier than a 1 bed place.

Geoff

 

So it turns out we are going to be in Cairns during the eclipse, so i thought i might try and get a photo or two.

Just have a 60d with 18-200. Whats the best filter to use to try and get a photo? A 72mm screw on would be best, but will try something else that will work.

 

For shots at totality, you won't need a filter. For shots of the sun at any other time (i.e. moon covering part of the sun), you will need a solar filter. You can make your own out of mylar film (or some other other materials), but Thousand Oaks make threaded solar filters to fit camera lenses - sold in Australia by www.myastroshop.com.au - they may not have any at this late stage, but worth trying.

 

Anybody in Cairns yet? Enjoying the weather?

We have some floor space available if anyone is desperate for accommodation, and have the next two evenings free if anyone wants to catch up for a beer.

 

Damn, didn't even know this was on. :/ Too late to arrange a trip up, but I'm looking forward to seeing what comes out of OCAU 'togs.

 

Gah, if only you posted last week. Had to cancel original Cairns trip due to family event which is now cancelled as well.

 

We were going to be up at a friend's house on one of the northern beaches, but my partner has a fed government job, and despite the minister regularly saying her area is "Overstaffed", they have refused all flex requests and have even gone to the effort of distributing all main roads and council road closure notices to the staff, and reinforced the requirement to be at work on time, even if it means staying the night in town. (Good luck getting accommodation that night!)

As a result, we are staying in town so she can guarantee she gets to work, which means we are able to host couchsurfers.