May 6, 2011 Rare Optics Display

Labeling some of these arcs can be tricky business if you don't know all the ins and outs like myself(as in I don't know them lol). Sun elevations matter and can eliminate some possibilities. Also how strong other optics are at the same time in relation can narrow it down. They have simulations you can mess with crystal types, with your known sun elevation. You tweak it until your overall display is there. I myself have done next to nothing with it though. I e-mail some with an expert in the field though and get some observations there, from Marko Riikonen. Most of what I've learned has come from there. You can also learn a lot on the atmospheric optics site. There is a good bit on the rare 46 degree halo there: http://www.atoptics.co.uk/halo/46orsup.html .

In the photo the main halo is easy, a 22 degree typical halo. I've seen the lower deal before, but usually really faint and short. This one was brighter and much longer and curved. It's not a circumhorizon arc, as seen by this page: http://www.atoptics.co.uk/halo/supim3.html . That and examples on the 46 degree page above. It wouldn't be curved.

But then it could be the infralateral arc. I'm really tired of trying to figure this particular lower one out, be it 46 degree halo or 46 infralateral. There is a simulation program on there but it's not easy to know what to start off entering. I've gotten some wild simulations off it though. I can get it to make these odd radius displays easy enough, but not just like this with the upper tangent part.

Whatever it is, it is there under the main 22 degree halo.

It's still there and now you can see the 9 degree halo inside the 22. Think this was around 2pm.

It's now later in the day. Here is an image heavily contrasted just for a guide purpose. 6 halos would be evident. The 35 degree really wasn't noticed with my eyes. You could see it on the stills on the camera though. In the upper left of the image you can see a lens flare. That is what is tricky on shooting things with an ultrawide. You can get a perfect circle lens flare that looks like a halo in the same area as the 46 degree. The thing to note on the way it flares then is it goes wider red out to a sharp cut off green then blue. The arc where it is labeled 46 was not a lens flare. You could see it with your eyes. I point at it in some photos to show that I could see it. I also cover the sun up with my hat in others, which would readily kill lens flaring.

Here is another heavily contrasted(USM) with 9 degree and 24 degree plate arcs labeled, thanks again to Marko. It's not like they are the most obvious and interesting things in the image. I'm simply making this with labels for my later reference. Otherwise I will forget and end up bugging Marko more than I already have. Between this big rare multiple display and the one in November 2010 last year, I now have a whole lot of the optics labeled and now know of them and to look for them. Next stop is knowing the crystal types and orientations as so I can enter it into the simulation software, with sun elevation, to replicate the displays with it. Pretty fascinating stuff once you get into it and catch a couple rare displays. To get the good clear displays, you kinda need either the arctic circle or ski resort snow machines. Neither overly close to here.

This is close as to visual appearance as I could get it. Faint 46 degree halo out there and also faint parhelic circle trying to form.

Hey a contrail shadow to add to the optics.

The 18/20 degree halo area shows up better in this one, just inside the 22. Probably more 18 degree than anything.

This is the natural look version of the second heavily contrasted image with labels up higher on the page. If you were to have been there and looking it'd be much like this. You can only barely notice 35 degree hints on the upper right side of where it is. The 46 was most obvious during this time. The 9 degree was obvious and crisp but it's not overly easy to see so close to the sun. Parhelic circle line pretty faint but there, as is the upper tangent.

You get lens flaring by bright light entering and reflecting internally. This is why they make lens hoods, for times you aren't pointing at the bright light(sol pointing at it) but the light still enters the side and bounces. You can put your hand up and block such light and watch your flaring go away. With my hat blocking the sun there would be no big circular flare like might otherwise happen. That outer halo is indeed there and visually looked about like that in this picture.You needed to lose some of the thicker cirrus to see it out there and this was the perfect timing of that, this window. Generally it was damn faint.

Also on this day, cirrus thickness didn't seem to matter much. For a while you'd have super bright 22 degree halo. Then later on it was a long time of nothing but with all sorts of varying degrees of cirrus. It seemed clear it wasn't so much the cirrus doing it, but ice crystals passing by in another layer. It reminded me a lot of how the day went in November with the crazy lowitz arc display. You'd look at the sky and be like, what the hell changed. Often on normal halo days it will be there when the cirrus is right and barely ever leave. Not so on this one and not so on the November one, both having a lot more going on than just a 22 degree halo.

There pointing at it lol. Not a lens flare. Course given all the other halos, they should probably point out its likeliness. And yes at the same time you can have the lens flare with the halo. I was doing my best to watch for the flare on the angle I was holding at and snap after I got rid of it.

It is not simple to process these to look most like it was at the time. The bright sun wants to blow out and also the dynamic range wants to shadow the rest of the scene. Some wide angle lens vignetting makes that even worse. Takes some carefully placed gradient tool adjustments in CS4. And some vignetting adjustments. They are actually pretty damn annoying to process. Getting a cooler white balance helps too. Which is probably the propper one anyway as the auto white balance wants to go too warm.

It's kinda fun to treat these all as a hunt, a game, where you try and bag as many as you can. But in this sense it can be a bit like counting tornadoes and getting more out of a number than a sight. I don't like that. But yet here I am with this optics stuff, basically doing just that lol. I have a huge list of optics bagged now, even if the displays haven't been mind blowing. Granted some aspects were pretty cool and some other less clear and intersting to look at optics came along for the ride.