Tagged: astro

8th June 2017 – Macro to Astro

Our speaker this week was Richard Price talking on the very small and the infinite (at least the bit of it we can see) – Macro to Astro. As ever a hugely informative and accessible evening given to a packed hall.

 

When talking Macro (on a ratio of reproduction to actual size of the subject of 1:1 or greater) we will be including what is close up photography too as there is a technical difference but not, as far as next meetings practical is concerned, no difference worth the time.

 

These are both areas of photography that appear complicated but, whilst demanding, they can be easily accessed. And they are both absorbing aspects of photography and being both accessible and demanding  they teach us a lot about our equipment and how light works with it. It also tells us a lot about our kit and can involve finding work arounds. For instance my manufacturers own 50mm lens will not work on anything but manual and with the depth of field preview button held down with my extension rings. My third party lenses work just fine. Took a while to work out how to get the nifty to work, but it was worth the effort. With a mirrorless camera like mine the DOF preview button is usually redundant -what you see in the view finder is exactly what you get as an image. Only it isn’t redundant at all and I am rather glad it’s there.

 

Of course, how near/far you want to go is a matter of budget but only really at the extremes. You can get some perfectly acceptable macro shots with a kit lens and a reversing ring (about £7 for a 52mm filter – size it’s written on the front of your lens, in the case of our 52mm example as Ø52).  You can also use a coupling ring to reverse one and add another lens to it to make a longer focal length and a greater degree of magnification. In both case it might be advisable to take any UV filters you have off the end of the lens.

 

The next option Rich gave us was using screw in filters (lenses) of varying dioptres. These are available for around £15 (and upwards depending on filter size), but as with everything else you get what you pay for. Essentially these are like reading glasses for your lens, they are lenses that fit on the end of  lenses. If you buy them for the largest filter size you have in your range of lenses you can buy a set of step down rings to fit them to your smaller filter sizes (usually for around £5).

 

Extension tubes, moving the lens away from the focal plane foreshortening its focusing capacity, use no intermediary glass at all, so there is no risk of flare or softening enhanced by putting more barriers between subject and sensor.  By shortening that distance  a degree of magnification results by getting closer to the subject. This is generally a more expensive route than the two previously discussed. this is because a certain amount of electronic communication has to be allowed for in the design of the tubes and this complicates the manufacturing process making it more expensive. It isn’t always effective either (see example given above) and work rounds result. However, the more you pay, generally, the more you get in terms of functionality and performance, though this is not an absolute guide.

 

Finally there is the most expensive option, the dedicated macro lens. Without a doubt this is the higher performer when it comes to producing quality of images in terms of sharpness and contrast, and without a doubt. But all that comes at a cost and even the cheapest all manual lenses cost several hundred pounds. Whichever route we go, macro/close up photography can be done anywhere and relatively easily and cheaply. One extra technique that might help is Focus Stacking. It can be done in Photoshop, as per the link, but failing that you might want to try CombineZP which is free and simple to use.

 

Now focus stacking as a technique makes a good link to the second half of our evening, Astro-photography. The reason being that photo stacking is an often used technique when taking photographs of the stars. It’s not an absolute requirement, though, and the basics are relatively straightforward. Rich recommended using StarStax, which is freeware, as you were wondering and developed with astro-photography in mind. But we get a little ahead of ourselves.

 

Dark areas in the UK are few and far between. Light pollution is a serious problem, not just for photographers but for wild life too, in our rather crowded island. Even in designated Dark Areas there are problems at the extremities where towns and villages emit a glow low on the horizon. So it takes some work.

 

The pollution part is best thought of as the light you would eliminate if you could. The night sky isn’t black, the horizon is always discernible.  The sky itself is also quite bright. If we are trying to record as much detail as possible (known as Deep Sky astrophotography) we are going to be fighting the noise generated by the sensor of the camera, especially at higher ISO’s but even at the lowest setting because where there is a signal there will be noise. If we treat the sky as black either by exposing or reducing it to black in post production then the fainter details are going to get lost. The point is the sky isn’t really black, it’s closer to a dirty orange colour. Because of the light pollution and the reflective nature of Earth’s atmosphere.

 

We can get round this in post by adjusting levels, picking the darkest part of our image as a start point with the eye dropper and adjusting the levels. It’s a matter of trial and error really. As is white balance. Regardless, this will all be a matter of trial and mostly error at the beginning and that is actually part of the fun. Learning new techniques like this means we learn more about the competencies and capabilities of our equipment and allows us to do more things with it.

 

Our thanks again to Richard and good luck as he takes this and his other presentations on the road.

 

 

N E X T  M E E T I NG

Macro and close up practical evening. Bring cameras tripods and that reversing ring you just ordered off Amazon.

 

 

 

 

23rd April 2015: From Macro to Astro

Astro, portrait- and macro-photography were the subjects of  our meeting this week and our thanks go out to all who contributed and to Richard Price in particular for his introduction to the Astro-photography presentation. Those of you inspired by his talk please note the postings on the club Facebook and Flickr pages for details of the proposed outings. This week’s blog is going to talk about some basics.

 

The basics of astrophotography are pretty straight forward. Yes you can buy specific cameras for it, Cannon 20DA (well probably not anymore) and 60Da were constructed with modified Infra Red (IR) filters so that other reds close in the spectrum weren’t affected so and thus the images presented are more realistic. No you don’t need to (unless overburdened with cash or taking this very seriously indeed) as long as you have a bulb setting on your camera and a rudimentary  grasp of the exposure triangle and access to a Manual mode, you can make a start. Of course patience, a little technique (including in post processing) and a willingness to experiment are also part of the deal as is  a tripod, but Richard reckons that a lens around f3.5 or faster and a cable release are the other things you need to get a start. Oh and no phobia’s about post processing. That is going to have to happen, though a relatively modest experience can get you some great results. It helps if you understand layers and masks, which, in essence, isn’t complicated, though the things you can do with them can be. They are not just confined to Photoshop, they can be found in other editors too, such as Gimp.  Going as dark as you can, by which I mean as little light pollution as can be found, is also useful, but there are some things you can do in light polluted areas (the darker the cloudless sky the better) Richard particularly concentrated on the Milky Way, though the Moon and a solar eclipse got honourable mentions long the way, as that is the hoped for subject of the photoshoot planned.

 

Portrait photography is not something we have really touched on in the blog, which, considering its presence in the field of photography is a little surprising, but we have done a lot of stuff around the subject in the club without addressing the specifics directly (by which I mean since I took the blog over).  Several members shared their images and experiences and thanks to Gerry in particular for the way he went through the process and reactions to the judge’s comments from the last round of the ROC (gallery pending, should be up in a separate post this week). There is a common misconception that you can’t “do” portraits properly unless you have a studio, enormous lighting rig, make-up and hair stylists and an enormous amount of gear. Whereas there are certainly people out there who would like to believe that, if not just to justify the outlay they have on these things which may not yet see a return in the quality of results, it most definitely is not. Different if it is how you make your living, however, and then it has to be the right gear for the situation.

 

The basics for portrait photography are the same as any other: a camera; a subject and a light source.   As ever, it is how you put these things together that counts. Taking each in turn: The camera is, as ever, the one you have. Yes there are tweaks and options you can generate through the choice of glass on a DSLR or similar, and the white balance and exposure settings, but the basics for composition remain constant.  As for subject, you want to do them justice, that means getting the best angle for the person you are shooting. The first  accessory you will probably buy is a 5 in 1 reflector.  The best accessory you will probably buy is a 5 in 1 reflector.  It is a good way of getting the light available to  where you need it. There are good reasons for investing in a studio set up (if you have the space) but there are DIY options too which are lighter on the pocket and from which decent results can be made. Learn the basic lighting set ups, get them off pat before moving on to something more advanced. At the centre of portrait photography though, the craft apart, is the relationship between subject and photographer. The better this works the more decent shots are likely, all other things remaining equal. It is as much part of the kit as speed lights, soft boxes or reflectors. It takes work on both sides of the camera for success.

 

Macro we touched upon in the Ask Reflex post so I will not rehash that, other than encourage you to give it a go if you haven’t and share Tim Cooper’s tip that the background is eveything. So a wide ranging evening with plenty to think about and a big club thank you to everyone who made it possible.

A N N O U N C E M E N T S

1. A reminder to join in the clubs monthly Flickr competion.

2. And whilst we are on the subject of Flickr, there is also a club Flickr space dedicated to giving suggestions to member’s photo’s they have posted. A good resource but only if you join in. There are some guidelines on constructive criticism, they are only suggestions but can be adapted. There is an image up there now looking for suggestions.

3. Next meeting we have a guest speaker, Philipa Wood. Get the skinny from Mr Painter here >>> Meeting 30th April 2015