equipment recommendation – What lens do I need to do super-close-up macro shots?

If you own a Canon camera, then to really do macro photography like that you probably want the MP-E 65mm f/2.8 1-5x Zoom Macro lens. Unlike most macro lenses which max out at a 1:1 reproduction ratio, which is usually not quite enough to get close-up shots of bug parts, the MP-E 65mm macro is a zoom macro. It supports a magnification ratio between as low as 1:1 and as high as 5:1, or 5x magnification. With the MP-E, which BTW is a lens entirely unique to Canon, you’ll be able to get those amazing super-close macro shots of insect eyes, “hair”, etc.

Alternatively, you want to get at least a “true macro” lens. The lens you have now is not a macro, which means you cannot even get a 1:1 magnification. Your lens is limited to less (probably much less) than 1:1 ratio, which greatly reduces the amount of detail you can get onto the sensor. Canon offers several macro lenses, including the EF 100mm f/2.8 Macro USM, the EF 100mm f/2.8 L IS Macro USM, and the EF 180mm f/3.5 L Macro, all of which support a true 1:1 magnification.

equipment recommendation – What is needed in order to produce good quality photographic wallpaper for a smallish room?

I am not a regular photographer. I’m interested in the idea of having a photographic harbour scene as wallpaper on my study wall. It may or may not be required fill the whole wall: I’ve given approximate dimensions below.

My understanding so far

An old-fashioned photo has resolution at a molecular scale and so, in my imagination, it could be blown up to be projected on the side of a building without noticeable loss of quality. Ergo, my study wall would not be a problem wrt resolution.

A digital photo is obviously limited to the number of pixels it can capture.

The printing process also has a limit to its resolution.


If I go along to my local harbour, what sort of camera do I need to hire or borrow in order to get a photo detailed enough to make wallpaper that will stand up to fairly close scrutiny?** Do I need analog or digital. What printing process can handle such large sheets?

Is there anything else I need to know?


**Note – The area in question is approximately 7ft 6inches (2.3m) high by 10 ft (3m) wide. I don’t want noticeable pixellation when viewing from 2 feet away.

design patterns – perspectives that undertake computational intelligence for modeling machine learning for video recommendation in intelligent e-learning system

1/ How are the techniques of machine learning able to improve the precision of automatic learning style identification? What recommendation decisions to be made for the intelligent e-learning system? What are the advantages and disadvantages of various automatons for the above mentioned e-learning system?

2/how would the increasing use of machine learning affect the intelligent software design needed in the context of design patterns (Observer DP, Command DP , State DP , Chain of responsibility DP , Template Method DP)?

3/what are perspectives that undertake computational intelligence for modeling machine learning technique for video recommendation in the e-learning recommendation system.

Looking for a recommendation to a good book/ tutorial series on deep dive into Spring WebFlux

I am new to reactive stack in Spring and have started developing reactive apps with Webflux + Reactive mongo together with Spring 2. But I always get stuck when finding solutions for some problem using WebFlux. I followed a basic tutorial from Udemy and Refer Project Reactor’s user documentation also.
But I need a recommendation to a book or a good tutorial series which does a deep dive to Spring WebFlux.

functional analysis – Reference Recommendation: Generalization of Dunford-Pettis in Various Settings

I have been coming across with Dunford-Pettis quite a bit recently. I have found Banach Lattice offers quite some generalization, and there are some nice things about Dunford-Pettis on Mackey topology. However, I wonder whether there are some more excellent results, or even better, a monograph dedicated to this topic. In the meantime, any applications would also be better.

Thanks a lot.

equipment recommendation – Camera suggesion for rostrum with SDK (and wifi)

I currently take photos of paperwork using an SLR mounted to a rostrum stand. I have written my own software which uses the Canon SDK to take photos of the paperwork, recognizing QR codes on the paperwork.

The camera I use is a Canon 5D Mark ii with an L lens. It’s total overkill for the job! I’d like to have a camera permanently setup for this purpose, and feel that there might be a domestic point-and-click camera which I could pick up second-hand that would do the job.

Does anyone know a camera that meets the following specs?

  • Take photos of A4 paper at a distance of 30-50cm. (I currently use my 17-40 L lens on the 35mm camera)
  • Can fit to a rostrum with a standard tripod thread.
  • Is powered over USB cable.
  • Has an SDK available that means that I can communicate with the camera over USB or WIFI to take and receive photos remotely?
  • Is inexpensive and available on the secondhand market.

equipment recommendation – Low budget camera for photojournalism

is someone using Canon EOS 7D for photojournalism? I have one for a year and I was thinking about upgrading my body (actually buying the next one and shoot action with two cameras. One with Canon 50mm and the next with Sigma 20mm and  I want to avoid lens changing). 

Question is if it’s worth to buy Canon EOD 5D Mark II. / 6D for 50mm lenses (80mm crop on 7D is too long for me). I wonder if only one cross-type AF point is enough for action photos of the protests when my 7D has 19 of them, so it’s an extreme downgrade. The 6D has also different controls when 7D and 5D Mk II has the same, but 5D has only one Digic 4, 7D has two of them. I want a full-frame camera cause of better image quality. (5D Mk III is out of my budget).

Thank you for your advice and opinion.

PS: I’m not really too afraid of changing the brand to Nikon or Sony.

(My photo from a protest in Prague, Czech Republic)
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software recommendation – Image viewer that can display all ICO sizes in a file

What are the image viewers available in Kubuntu that are able to display all ICO sizes in a file?

In Windows 7 Picture Viewer, I can use PAGE UP / PAGE DOWN to navigate on the “mipmaps” (or whatever it’s called) of an ICO file. It seems I can’t do that on EOG, Gwenview, or even Pinta.

I’m looking for a viewer, but if you know of an editor that allows to edit each size independently, that would be nice too.

equipment recommendation – Alternatives to a6400 and sigma 30/56 mm lenses for Instagram portrait/landscape pictures?

I currently want to get a camera for Instagram for portrait (85 mm equivalent) and full body/landscape/street photography (50 mm equivalent seems to be recommended for all around)

It seems like the a6400 would work well my for use case, and the sigma 56 and 30 are the recommendation from dpreview’s best lenses:

The a6400 (~750 used, 900 new), sigma 56 (300, 400) and sigma 30 (250, 300) come out to around $1300 used – $1600 new

For camera and lens requirements for me:

Important: Good autofocus, flip out screen

Nice-to-have: Low light performance, portability

I have looked into Fuji cameras, but it seems the equivalent lenses are more expensive than sony counterparts. I looked at the Canon EOS RP but it also seemed like lenses for it were more expensive as well. Though admittedly I don’t have too much familiarity with those cameras, so I may be missing something.

My questions are

  1. Is there a better alternative for $1300 used – $1600 new to the a6400 and sigma 30/56 for Instagram portrait/landscape pictures

  2. Am I spending too much if I only plan on using this camera for online Instagram and not prints? If there are less expensive alternatives that fit this use case, I would be happy to hear them.

equipment recommendation – How can I take pictures at preset times throughout a day?

I need to take a close up picture of an object at up to 8 different, pre-programmed times a day (i.e. 6:00am, 7:00am, 7:30am, 12:00pm, 2:30pm, 6:00pm, 7:00pm, 8:00pm).

I have looked at trail cameras but they seem to be mostly motion triggered.
Intervalometers seem to be only programmable at time intervals like every so many hours.

I will have Wifi access at the camera location and would like to minimize costs.